diff --git a/app/scripts/controllers/ens/index.js b/app/scripts/controllers/ens/index.js
index a7d4c696b..85477ef7e 100644
--- a/app/scripts/controllers/ens/index.js
+++ b/app/scripts/controllers/ens/index.js
@@ -1,8 +1,8 @@
 import punycode from 'punycode/punycode';
-import { toChecksumAddress } from 'ethereumjs-util';
 import { ObservableStore } from '@metamask/obs-store';
 import log from 'loglevel';
 import { CHAIN_ID_TO_NETWORK_ID_MAP } from '../../../../shared/constants/network';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 import Ens from './ens';
 
 const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000';
@@ -43,7 +43,7 @@ export default class EnsController {
   }
 
   reverseResolveAddress(address) {
-    return this._reverseResolveAddress(toChecksumAddress(address));
+    return this._reverseResolveAddress(toChecksumHexAddress(address));
   }
 
   async _reverseResolveAddress(address) {
@@ -79,7 +79,7 @@ export default class EnsController {
       return undefined;
     }
 
-    if (toChecksumAddress(registeredAddress) !== address) {
+    if (toChecksumHexAddress(registeredAddress) !== address) {
       return undefined;
     }
 
diff --git a/app/scripts/controllers/token-rates.js b/app/scripts/controllers/token-rates.js
index b725b04c9..1bba3f389 100644
--- a/app/scripts/controllers/token-rates.js
+++ b/app/scripts/controllers/token-rates.js
@@ -1,8 +1,8 @@
 import { ObservableStore } from '@metamask/obs-store';
 import log from 'loglevel';
 import { normalize as normalizeAddress } from 'eth-sig-util';
-import { toChecksumAddress } from 'ethereumjs-util';
 import getFetchWithTimeout from '../../../shared/modules/fetch-with-timeout';
+import { toChecksumHexAddress } from '../../../shared/modules/hexstring-utils';
 
 const fetchWithTimeout = getFetchWithTimeout(30000);
 
@@ -45,7 +45,7 @@ export default class TokenRatesController {
         this._tokens.forEach((token) => {
           const price =
             prices[token.address.toLowerCase()] ||
-            prices[toChecksumAddress(token.address)];
+            prices[toChecksumHexAddress(token.address)];
           contractExchangeRates[normalizeAddress(token.address)] = price
             ? price[nativeCurrency]
             : 0;
diff --git a/app/scripts/metamask-controller.js b/app/scripts/metamask-controller.js
index 00b3115c8..93faa0b48 100644
--- a/app/scripts/metamask-controller.js
+++ b/app/scripts/metamask-controller.js
@@ -10,7 +10,7 @@ import createSubscriptionManager from 'eth-json-rpc-filters/subscriptionManager'
 import providerAsMiddleware from 'eth-json-rpc-middleware/providerAsMiddleware';
 import KeyringController from 'eth-keyring-controller';
 import { Mutex } from 'await-semaphore';
-import { toChecksumAddress, stripHexPrefix } from 'ethereumjs-util';
+import { stripHexPrefix } from 'ethereumjs-util';
 import log from 'loglevel';
 import TrezorKeyring from 'eth-trezor-keyring';
 import LedgerBridgeKeyring from '@metamask/eth-ledger-bridge-keyring';
@@ -27,6 +27,7 @@ import {
 import { TRANSACTION_STATUSES } from '../../shared/constants/transaction';
 import { MAINNET_CHAIN_ID } from '../../shared/constants/network';
 import { UI_NOTIFICATIONS } from '../../shared/notifications';
+import { toChecksumHexAddress } from '../../shared/modules/hexstring-utils';
 
 import ComposableObservableStore from './lib/ComposableObservableStore';
 import AccountTracker from './lib/account-tracker';
@@ -1107,14 +1108,14 @@ export default class MetamaskController extends EventEmitter {
     // Filter ERC20 tokens
     const filteredAccountTokens = {};
     Object.keys(accountTokens).forEach((address) => {
-      const checksummedAddress = toChecksumAddress(address);
+      const checksummedAddress = toChecksumHexAddress(address);
       filteredAccountTokens[checksummedAddress] = {};
       Object.keys(accountTokens[address]).forEach((chainId) => {
         filteredAccountTokens[checksummedAddress][chainId] =
           chainId === MAINNET_CHAIN_ID
             ? accountTokens[address][chainId].filter(
                 ({ address: tokenAddress }) => {
-                  const checksumAddress = toChecksumAddress(tokenAddress);
+                  const checksumAddress = toChecksumHexAddress(tokenAddress);
                   return contractMap[checksumAddress]
                     ? contractMap[checksumAddress].erc20
                     : true;
@@ -1151,10 +1152,10 @@ export default class MetamaskController extends EventEmitter {
     const accounts = {
       hd: hdAccounts
         .filter((item, pos) => hdAccounts.indexOf(item) === pos)
-        .map((address) => toChecksumAddress(address)),
+        .map((address) => toChecksumHexAddress(address)),
       simpleKeyPair: simpleKeyPairAccounts
         .filter((item, pos) => simpleKeyPairAccounts.indexOf(item) === pos)
-        .map((address) => toChecksumAddress(address)),
+        .map((address) => toChecksumHexAddress(address)),
       ledger: [],
       trezor: [],
     };
@@ -1164,7 +1165,7 @@ export default class MetamaskController extends EventEmitter {
     let { transactions } = this.txController.store.getState();
     // delete tx for other accounts that we're not importing
     transactions = Object.values(transactions).filter((tx) => {
-      const checksummedTxFrom = toChecksumAddress(tx.txParams.from);
+      const checksummedTxFrom = toChecksumHexAddress(tx.txParams.from);
       return accounts.hd.includes(checksummedTxFrom);
     });
 
diff --git a/app/scripts/migrations/039.js b/app/scripts/migrations/039.js
index 7dcf904de..aa288553a 100644
--- a/app/scripts/migrations/039.js
+++ b/app/scripts/migrations/039.js
@@ -1,5 +1,5 @@
 import { cloneDeep } from 'lodash';
-import { toChecksumAddress } from 'ethereumjs-util';
+import { toChecksumHexAddress } from '../../../shared/modules/hexstring-utils';
 
 const version = 39;
 
@@ -12,7 +12,7 @@ function isOldDai(token = {}) {
     token &&
     typeof token === 'object' &&
     token.symbol === DAI_V1_TOKEN_SYMBOL &&
-    toChecksumAddress(token.address) === DAI_V1_CONTRACT_ADDRESS
+    toChecksumHexAddress(token.address) === DAI_V1_CONTRACT_ADDRESS
   );
 }
 
diff --git a/shared/modules/hexstring-utils.js b/shared/modules/hexstring-utils.js
index f40f537d3..1f895a3c7 100644
--- a/shared/modules/hexstring-utils.js
+++ b/shared/modules/hexstring-utils.js
@@ -3,6 +3,7 @@ import {
   isValidAddress,
   isValidChecksumAddress,
   addHexPrefix,
+  toChecksumAddress,
 } from 'ethereumjs-util';
 
 export const BURN_ADDRESS = '0x0000000000000000000000000000000000000000';
@@ -51,3 +52,22 @@ export function isValidHexAddress(
 
   return isValidAddress(addressToCheck);
 }
+
+export function toChecksumHexAddress(address) {
+  if (!address) {
+    // our internal checksumAddress function that this method replaces would
+    // return an empty string for nullish input. If any direct usages of
+    // ethereumjs-util.toChecksumAddress were called with nullish input it
+    // would have resulted in an error on version 5.1.
+    return '';
+  }
+  const hexPrefixed = addHexPrefix(address);
+  if (!isHexString(hexPrefixed)) {
+    // Version 5.1 of ethereumjs-utils would have returned '0xY' for input 'y'
+    // but we shouldn't waste effort trying to change case on a clearly invalid
+    // string. Instead just return the hex prefixed original string which most
+    // closely mimics the original behavior.
+    return hexPrefixed;
+  }
+  return toChecksumAddress(addHexPrefix(address));
+}
diff --git a/ui/app/components/app/account-list-item/account-list-item-component.test.js b/ui/app/components/app/account-list-item/account-list-item-component.test.js
index 11d5ba6eb..d8a05ce46 100644
--- a/ui/app/components/app/account-list-item/account-list-item-component.test.js
+++ b/ui/app/components/app/account-list-item/account-list-item-component.test.js
@@ -1,18 +1,19 @@
 import React from 'react';
 import { shallow } from 'enzyme';
 import sinon from 'sinon';
-import * as utils from '../../../helpers/utils/util';
 import Identicon from '../../ui/identicon';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 import AccountListItem from './account-list-item';
 
+jest.mock('../../../../shared/modules/hexstring-utils', () => ({
+  toChecksumHexAddress: jest.fn(() => 'mockCheckSumAddress'),
+}));
+
 describe('AccountListItem Component', () => {
-  let wrapper, propsMethodSpies, checksumAddressStub;
+  let wrapper, propsMethodSpies;
 
   describe('render', () => {
     beforeAll(() => {
-      checksumAddressStub = sinon
-        .stub(utils, 'checksumAddress')
-        .returns('mockCheckSumAddress');
       propsMethodSpies = {
         handleClick: sinon.spy(),
       };
@@ -36,7 +37,6 @@ describe('AccountListItem Component', () => {
 
     afterEach(() => {
       propsMethodSpies.handleClick.resetHistory();
-      checksumAddressStub.resetHistory();
     });
 
     afterAll(() => {
@@ -126,9 +126,7 @@ describe('AccountListItem Component', () => {
       expect(
         wrapper.find('.account-list-item__account-address').text(),
       ).toStrictEqual('mockCheckSumAddress');
-      expect(checksumAddressStub.getCall(0).args).toStrictEqual([
-        'mockAddress',
-      ]);
+      expect(toChecksumHexAddress).toHaveBeenCalledWith('mockAddress');
     });
 
     it('should not render the account address as a checksumAddress if displayAddress is false', () => {
diff --git a/ui/app/components/app/account-list-item/account-list-item.js b/ui/app/components/app/account-list-item/account-list-item.js
index 9b0c0e38f..5220dede9 100644
--- a/ui/app/components/app/account-list-item/account-list-item.js
+++ b/ui/app/components/app/account-list-item/account-list-item.js
@@ -1,8 +1,8 @@
 import React from 'react';
 import PropTypes from 'prop-types';
-import { checksumAddress } from '../../../helpers/utils/util';
 import Identicon from '../../ui/identicon';
 import AccountMismatchWarning from '../../ui/account-mismatch-warning/account-mismatch-warning.component';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 
 export default function AccountListItem({
   account,
@@ -34,7 +34,7 @@ export default function AccountListItem({
 
       {displayAddress && name && (
         <div className="account-list-item__account-address">
-          {checksumAddress(address)}
+          {toChecksumHexAddress(address)}
         </div>
       )}
     </div>
diff --git a/ui/app/components/app/modals/export-private-key-modal/export-private-key-modal.component.js b/ui/app/components/app/modals/export-private-key-modal/export-private-key-modal.component.js
index 6ac5219b3..ba6e4ca8b 100644
--- a/ui/app/components/app/modals/export-private-key-modal/export-private-key-modal.component.js
+++ b/ui/app/components/app/modals/export-private-key-modal/export-private-key-modal.component.js
@@ -4,10 +4,10 @@ import React, { Component } from 'react';
 
 import { stripHexPrefix } from 'ethereumjs-util';
 import copyToClipboard from 'copy-to-clipboard';
-import { checksumAddress } from '../../../../helpers/utils/util';
 import ReadOnlyInput from '../../../ui/readonly-input';
 import Button from '../../../ui/button';
 import AccountModalContainer from '../account-modal-container';
+import { toChecksumHexAddress } from '../../../../../shared/modules/hexstring-utils';
 
 export default class ExportPrivateKeyModal extends Component {
   static contextTypes = {
@@ -149,7 +149,7 @@ export default class ExportPrivateKeyModal extends Component {
         <span className="export-private-key-modal__account-name">{name}</span>
         <ReadOnlyInput
           wrapperClass="ellip-address-wrapper"
-          value={checksumAddress(address)}
+          value={toChecksumHexAddress(address)}
         />
         <div className="export-private-key-modal__divider" />
         <span className="export-private-key-modal__body-title">
diff --git a/ui/app/components/app/selected-account/selected-account.component.js b/ui/app/components/app/selected-account/selected-account.component.js
index f703678a1..b52dd033f 100644
--- a/ui/app/components/app/selected-account/selected-account.component.js
+++ b/ui/app/components/app/selected-account/selected-account.component.js
@@ -1,9 +1,10 @@
 import React, { Component } from 'react';
 import PropTypes from 'prop-types';
 import copyToClipboard from 'copy-to-clipboard';
-import { shortenAddress, checksumAddress } from '../../../helpers/utils/util';
+import { shortenAddress } from '../../../helpers/utils/util';
 
 import Tooltip from '../../ui/tooltip';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 
 class SelectedAccount extends Component {
   state = {
@@ -32,7 +33,7 @@ class SelectedAccount extends Component {
   render() {
     const { t } = this.context;
     const { selectedIdentity } = this.props;
-    const checksummedAddress = checksumAddress(selectedIdentity.address);
+    const checksummedAddress = toChecksumHexAddress(selectedIdentity.address);
 
     return (
       <div className="selected-account">
diff --git a/ui/app/components/app/transaction-list-item-details/transaction-list-item-details.container.js b/ui/app/components/app/transaction-list-item-details/transaction-list-item-details.container.js
index 4a96082c7..280cec020 100644
--- a/ui/app/components/app/transaction-list-item-details/transaction-list-item-details.container.js
+++ b/ui/app/components/app/transaction-list-item-details/transaction-list-item-details.container.js
@@ -1,10 +1,10 @@
 import { connect } from 'react-redux';
-import { checksumAddress } from '../../../helpers/utils/util';
 import { tryReverseResolveAddress } from '../../../store/actions';
 import {
   getAddressBook,
   getRpcPrefsForCurrentProvider,
 } from '../../../selectors';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 import TransactionListItemDetails from './transaction-list-item-details.component';
 
 const mapStateToProps = (state, ownProps) => {
@@ -13,7 +13,7 @@ const mapStateToProps = (state, ownProps) => {
   const { recipientAddress, senderAddress } = ownProps;
   let recipientEns;
   if (recipientAddress) {
-    const address = checksumAddress(recipientAddress);
+    const address = toChecksumHexAddress(recipientAddress);
     recipientEns = ensResolutionsByAddress[address] || '';
   }
   const addressBook = getAddressBook(state);
diff --git a/ui/app/components/ui/identicon/identicon.component.js b/ui/app/components/ui/identicon/identicon.component.js
index ec2cc70cc..dd6eb5beb 100644
--- a/ui/app/components/ui/identicon/identicon.component.js
+++ b/ui/app/components/ui/identicon/identicon.component.js
@@ -2,9 +2,8 @@ import React, { PureComponent } from 'react';
 import PropTypes from 'prop-types';
 import classnames from 'classnames';
 import contractMap from '@metamask/contract-metadata';
-import { isHexString, addHexPrefix } from 'ethereumjs-util';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 
-import { checksumAddress } from '../../../helpers/utils/util';
 import Jazzicon from '../jazzicon';
 import BlockieIdenticon from './blockieIdenticon';
 
@@ -86,11 +85,9 @@ export default class Identicon extends PureComponent {
     }
 
     if (address) {
-      const checksummedAddress =
-        isHexString(addHexPrefix(address)) &&
-        checksumAddress(addHexPrefix(address));
+      const checksummedAddress = toChecksumHexAddress(address);
 
-      if (contractMap[checksummedAddress]?.logo) {
+      if (checksummedAddress && contractMap[checksummedAddress]?.logo) {
         return this.renderJazzicon();
       }
 
diff --git a/ui/app/components/ui/qr-code/qr-code.js b/ui/app/components/ui/qr-code/qr-code.js
index 6c00f33fc..db0eeed2c 100644
--- a/ui/app/components/ui/qr-code/qr-code.js
+++ b/ui/app/components/ui/qr-code/qr-code.js
@@ -4,7 +4,7 @@ import qrCode from 'qrcode-generator';
 import { connect } from 'react-redux';
 import { isHexPrefixed } from 'ethereumjs-util';
 import ReadOnlyInput from '../readonly-input/readonly-input';
-import { checksumAddress } from '../../../helpers/utils/util';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 
 export default connect(mapStateToProps)(QrCodeView);
 
@@ -20,9 +20,9 @@ function mapStateToProps(state) {
 function QrCodeView(props) {
   const { Qr, warning } = props;
   const { message, data } = Qr;
-  const address = `${isHexPrefixed(data) ? 'ethereum:' : ''}${checksumAddress(
-    data,
-  )}`;
+  const address = `${
+    isHexPrefixed(data) ? 'ethereum:' : ''
+  }${toChecksumHexAddress(data)}`;
   const qrImage = qrCode(4, 'M');
   qrImage.addData(address);
   qrImage.make();
@@ -50,7 +50,7 @@ function QrCodeView(props) {
       <ReadOnlyInput
         wrapperClass="ellip-address-wrapper"
         autoFocus
-        value={checksumAddress(data)}
+        value={toChecksumHexAddress(data)}
       />
     </div>
   );
diff --git a/ui/app/components/ui/sender-to-recipient/sender-to-recipient.component.js b/ui/app/components/ui/sender-to-recipient/sender-to-recipient.component.js
index 00e099e24..30e42e46f 100644
--- a/ui/app/components/ui/sender-to-recipient/sender-to-recipient.component.js
+++ b/ui/app/components/ui/sender-to-recipient/sender-to-recipient.component.js
@@ -4,9 +4,10 @@ import classnames from 'classnames';
 import copyToClipboard from 'copy-to-clipboard';
 import Tooltip from '../tooltip';
 import Identicon from '../identicon';
-import { checksumAddress, shortenAddress } from '../../../helpers/utils/util';
+import { shortenAddress } from '../../../helpers/utils/util';
 import AccountMismatchWarning from '../account-mismatch-warning/account-mismatch-warning.component';
 import { useI18nContext } from '../../../hooks/useI18nContext';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 import {
   DEFAULT_VARIANT,
   CARDS_VARIANT,
@@ -56,7 +57,10 @@ function SenderAddress({
     >
       {!addressOnly && (
         <div className="sender-to-recipient__sender-icon">
-          <Identicon address={checksumAddress(senderAddress)} diameter={24} />
+          <Identicon
+            address={toChecksumHexAddress(senderAddress)}
+            diameter={24}
+          />
         </div>
       )}
       <Tooltip
@@ -203,8 +207,8 @@ export default function SenderToRecipient({
   warnUserOnAccountMismatch,
 }) {
   const t = useI18nContext();
-  const checksummedSenderAddress = checksumAddress(senderAddress);
-  const checksummedRecipientAddress = checksumAddress(recipientAddress);
+  const checksummedSenderAddress = toChecksumHexAddress(senderAddress);
+  const checksummedRecipientAddress = toChecksumHexAddress(recipientAddress);
 
   return (
     <div className={classnames('sender-to-recipient', variantHash[variant])}>
diff --git a/ui/app/helpers/utils/util.js b/ui/app/helpers/utils/util.js
index cea0777a6..512acaef8 100644
--- a/ui/app/helpers/utils/util.js
+++ b/ui/app/helpers/utils/util.js
@@ -12,6 +12,7 @@ import {
   RINKEBY_CHAIN_ID,
   ROPSTEN_CHAIN_ID,
 } from '../../../../shared/constants/network';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 
 // formatData :: ( date: <Unix Timestamp> ) -> String
 export function formatDate(date, format = "M/d/y 'at' T") {
@@ -67,7 +68,7 @@ export function addressSummary(
   if (!address) {
     return '';
   }
-  let checked = checksumAddress(address);
+  let checked = toChecksumHexAddress(address);
   if (!includeHex) {
     checked = ethUtil.stripHexPrefix(checked);
   }
@@ -195,18 +196,6 @@ export function exportAsFile(filename, data, type = 'text/csv') {
   }
 }
 
-/**
- * Safely checksumms a potentially-null address
- *
- * @param {string} [address] - address to checksum
- * @returns {string} checksummed address
- *
- */
-export function checksumAddress(address) {
-  const checksummed = address ? ethUtil.toChecksumAddress(address) : '';
-  return checksummed;
-}
-
 /**
  * Shortens an Ethereum address for display, preserving the beginning and end.
  * Returns the given address if it is no longer than 10 characters.
diff --git a/ui/app/hooks/useTokensToSearch.js b/ui/app/hooks/useTokensToSearch.js
index 4542882f0..e4bc6495e 100644
--- a/ui/app/hooks/useTokensToSearch.js
+++ b/ui/app/hooks/useTokensToSearch.js
@@ -3,7 +3,6 @@ import { useSelector } from 'react-redux';
 import contractMap from '@metamask/contract-metadata';
 import BigNumber from 'bignumber.js';
 import { isEqual, shuffle } from 'lodash';
-import { checksumAddress } from '../helpers/utils/util';
 import { getTokenFiatAmount } from '../helpers/utils/token-util';
 import {
   getTokenExchangeRates,
@@ -14,6 +13,7 @@ import {
 } from '../selectors';
 import { getSwapsTokens } from '../ducks/swaps/swaps';
 import { isSwapsDefaultTokenSymbol } from '../../../shared/modules/swaps.utils';
+import { toChecksumHexAddress } from '../../../shared/modules/hexstring-utils';
 import { useEqualityCheck } from './useEqualityCheck';
 
 const tokenList = shuffle(
@@ -58,12 +58,12 @@ export function getRenderableTokenData(
     ) || '';
   const usedIconUrl =
     iconUrl ||
-    (contractMap[checksumAddress(address)] &&
-      `images/contract/${contractMap[checksumAddress(address)].logo}`);
+    (contractMap[toChecksumHexAddress(address)] &&
+      `images/contract/${contractMap[toChecksumHexAddress(address)].logo}`);
   return {
     ...token,
     primaryLabel: symbol,
-    secondaryLabel: name || contractMap[checksumAddress(address)]?.name,
+    secondaryLabel: name || contractMap[toChecksumHexAddress(address)]?.name,
     rightPrimaryLabel:
       string && `${new BigNumber(string).round(6).toString()} ${symbol}`,
     rightSecondaryLabel: formattedFiat,
@@ -71,7 +71,7 @@ export function getRenderableTokenData(
     identiconAddress: usedIconUrl ? null : address,
     balance,
     decimals,
-    name: name || contractMap[checksumAddress(address)]?.name,
+    name: name || contractMap[toChecksumHexAddress(address)]?.name,
     rawFiat,
   };
 }
diff --git a/ui/app/pages/confirm-transaction-base/confirm-transaction-base.container.js b/ui/app/pages/confirm-transaction-base/confirm-transaction-base.container.js
index 7a761bd9b..48d4ff814 100644
--- a/ui/app/pages/confirm-transaction-base/confirm-transaction-base.container.js
+++ b/ui/app/pages/confirm-transaction-base/confirm-transaction-base.container.js
@@ -23,11 +23,7 @@ import { getHexGasTotal } from '../../helpers/utils/confirm-tx.util';
 import { isBalanceSufficient, calcGasTotal } from '../send/send.utils';
 import { conversionGreaterThan } from '../../helpers/utils/conversion-util';
 import { MIN_GAS_LIMIT_DEC } from '../send/send.constants';
-import {
-  checksumAddress,
-  shortenAddress,
-  valuesFor,
-} from '../../helpers/utils/util';
+import { shortenAddress, valuesFor } from '../../helpers/utils/util';
 import {
   getAdvancedInlineGasShown,
   getCustomNonceValue,
@@ -40,6 +36,7 @@ import {
 } from '../../selectors';
 import { getMostRecentOverviewPage } from '../../ducks/history/history';
 import { transactionMatchesNetwork } from '../../../../shared/modules/transaction.utils';
+import { toChecksumHexAddress } from '../../../../shared/modules/hexstring-utils';
 import ConfirmTransactionBase from './confirm-transaction-base.component';
 
 const casedContractMap = Object.keys(contractMap).reduce((acc, base) => {
@@ -104,9 +101,9 @@ const mapStateToProps = (state, ownProps) => {
   const toName =
     identities[toAddress]?.name ||
     casedContractMap[toAddress]?.name ||
-    shortenAddress(checksumAddress(toAddress));
+    shortenAddress(toChecksumHexAddress(toAddress));
 
-  const checksummedAddress = checksumAddress(toAddress);
+  const checksummedAddress = toChecksumHexAddress(toAddress);
   const addressBookObject = addressBook[checksummedAddress];
   const toEns = ensResolutionsByAddress[checksummedAddress] || '';
   const toNickname = addressBookObject ? addressBookObject.name : '';
diff --git a/ui/app/pages/send/send-content/add-recipient/add-recipient.js b/ui/app/pages/send/send-content/add-recipient/add-recipient.js
index c1fee499b..5141fda1d 100644
--- a/ui/app/pages/send/send-content/add-recipient/add-recipient.js
+++ b/ui/app/pages/send/send-content/add-recipient/add-recipient.js
@@ -1,4 +1,3 @@
-import { toChecksumAddress } from 'ethereumjs-util';
 import contractMap from '@metamask/contract-metadata';
 import { isConfusing } from 'unicode-confusables';
 import {
@@ -19,6 +18,7 @@ import {
 import {
   isBurnAddress,
   isValidHexAddress,
+  toChecksumHexAddress,
 } from '../../../../../shared/modules/hexstring-utils';
 
 export function getToErrorObject(to, sendTokenAddress, chainId) {
@@ -44,7 +44,8 @@ export function getToWarningObject(to, tokens = [], sendToken = null) {
   let toWarning = null;
   if (
     sendToken &&
-    (toChecksumAddress(to) in contractMap || checkExistingAddresses(to, tokens))
+    (toChecksumHexAddress(to) in contractMap ||
+      checkExistingAddresses(to, tokens))
   ) {
     toWarning = KNOWN_RECIPIENT_ADDRESS_ERROR;
   } else if (isValidDomainName(to) && isConfusing(to)) {
diff --git a/ui/app/pages/send/send-content/add-recipient/add-recipient.utils.test.js b/ui/app/pages/send/send-content/add-recipient/add-recipient.utils.test.js
index 67a87bced..6f7688fa0 100644
--- a/ui/app/pages/send/send-content/add-recipient/add-recipient.utils.test.js
+++ b/ui/app/pages/send/send-content/add-recipient/add-recipient.utils.test.js
@@ -23,6 +23,7 @@ jest.mock('../../../../../shared/modules/hexstring-utils', () => ({
     Boolean(to.match(/^[0xabcdef123456798]+$/u)),
   ),
   isBurnAddress: jest.fn(() => false),
+  toChecksumHexAddress: jest.fn((input) => input),
 }));
 
 describe('add-recipient utils', () => {
diff --git a/ui/app/pages/settings/contact-list-tab/view-contact/view-contact.container.js b/ui/app/pages/settings/contact-list-tab/view-contact/view-contact.container.js
index 06a753446..275273d0a 100644
--- a/ui/app/pages/settings/contact-list-tab/view-contact/view-contact.container.js
+++ b/ui/app/pages/settings/contact-list-tab/view-contact/view-contact.container.js
@@ -2,11 +2,11 @@ import { compose } from 'redux';
 import { connect } from 'react-redux';
 import { withRouter } from 'react-router-dom';
 import { getAddressBookEntry } from '../../../../selectors';
-import { checksumAddress } from '../../../../helpers/utils/util';
 import {
   CONTACT_EDIT_ROUTE,
   CONTACT_LIST_ROUTE,
 } from '../../../../helpers/constants/routes';
+import { toChecksumHexAddress } from '../../../../../shared/modules/hexstring-utils';
 import ViewContact from './view-contact.component';
 
 const mapStateToProps = (state, ownProps) => {
@@ -25,7 +25,7 @@ const mapStateToProps = (state, ownProps) => {
   return {
     name,
     address: contact ? address : null,
-    checkSummedAddress: checksumAddress(address),
+    checkSummedAddress: toChecksumHexAddress(address),
     memo,
     editRoute: CONTACT_EDIT_ROUTE,
     listRoute: CONTACT_LIST_ROUTE,
diff --git a/ui/app/selectors/selectors.js b/ui/app/selectors/selectors.js
index 73cebf8db..e5de40dae 100644
--- a/ui/app/selectors/selectors.js
+++ b/ui/app/selectors/selectors.js
@@ -13,11 +13,7 @@ import {
   ALLOWED_SWAPS_CHAIN_IDS,
 } from '../../../shared/constants/swaps';
 
-import {
-  shortenAddress,
-  checksumAddress,
-  getAccountByAddress,
-} from '../helpers/utils/util';
+import { shortenAddress, getAccountByAddress } from '../helpers/utils/util';
 import {
   getValueFromWeiHex,
   hexToDecimal,
@@ -25,6 +21,7 @@ import {
 
 import { TEMPLATED_CONFIRMATION_MESSAGE_TYPES } from '../pages/confirmation/templates';
 
+import { toChecksumHexAddress } from '../../shared/modules/hexstring-utils';
 import { getNativeCurrency } from './send';
 
 /**
@@ -241,7 +238,7 @@ export function getAddressBook(state) {
 export function getAddressBookEntry(state, address) {
   const addressBook = getAddressBook(state);
   const entry = addressBook.find(
-    (contact) => contact.address === checksumAddress(address),
+    (contact) => contact.address === toChecksumHexAddress(address),
   );
   return entry;
 }
diff --git a/ui/app/store/actions.js b/ui/app/store/actions.js
index 2d404f52f..cbd90fe84 100644
--- a/ui/app/store/actions.js
+++ b/ui/app/store/actions.js
@@ -3,7 +3,6 @@ import pify from 'pify';
 import log from 'loglevel';
 import { capitalize } from 'lodash';
 import getBuyEthUrl from '../../../app/scripts/lib/buy-eth-url';
-import { checksumAddress } from '../helpers/utils/util';
 import { calcTokenBalance, estimateGasForSend } from '../pages/send/send.utils';
 import {
   fetchLocale,
@@ -27,6 +26,7 @@ import {
 import { switchedToUnconnectedAccount } from '../ducks/alerts/unconnected-account';
 import { getUnconnectedAccountAlertEnabledness } from '../ducks/metamask/metamask';
 import { LISTED_CONTRACT_ADDRESSES } from '../../../shared/constants/tokens';
+import { toChecksumHexAddress } from '../../../shared/modules/hexstring-utils';
 import * as actionConstants from './actionConstants';
 
 let background = null;
@@ -1729,7 +1729,7 @@ export function addToAddressBook(recipient, nickname = '', memo = '') {
     let set;
     try {
       set = await promisifiedBackground.setAddressBook(
-        checksumAddress(recipient),
+        toChecksumHexAddress(recipient),
         nickname,
         chainId,
         memo,
@@ -1755,7 +1755,7 @@ export function removeFromAddressBook(chainId, addressToRemove) {
   return async () => {
     await promisifiedBackground.removeFromAddressBook(
       chainId,
-      checksumAddress(addressToRemove),
+      toChecksumHexAddress(addressToRemove),
     );
   };
 }
diff --git a/ui/lib/icon-factory.js b/ui/lib/icon-factory.js
index ac9a035d2..132f5330d 100644
--- a/ui/lib/icon-factory.js
+++ b/ui/lib/icon-factory.js
@@ -1,7 +1,8 @@
 import contractMap from '@metamask/contract-metadata';
-import { isHexString, addHexPrefix } from 'ethereumjs-util';
-import { isValidHexAddress } from '../../shared/modules/hexstring-utils';
-import { checksumAddress } from '../app/helpers/utils/util';
+import {
+  isValidHexAddress,
+  toChecksumHexAddress,
+} from '../../shared/modules/hexstring-utils';
 
 let iconFactory;
 
@@ -18,11 +19,7 @@ function IconFactory(jazzicon) {
 }
 
 IconFactory.prototype.iconForAddress = function (address, diameter) {
-  let addr = address;
-
-  if (isHexString(addHexPrefix(address))) {
-    addr = checksumAddress(addHexPrefix(address));
-  }
+  const addr = toChecksumHexAddress(address);
 
   if (iconExistsFor(addr)) {
     return imageElFor(addr);