diff --git a/ui/app/components/customize-gas-modal/index.js b/ui/app/components/customize-gas-modal/index.js
index 744891c47..710ee24c0 100644
--- a/ui/app/components/customize-gas-modal/index.js
+++ b/ui/app/components/customize-gas-modal/index.js
@@ -6,23 +6,46 @@ const actions = require('../../actions')
 const GasModalCard = require('./gas-modal-card')
 
 const {
-  MIN_GAS_PRICE,
-  MIN_GAS_LIMIT,
+  MIN_GAS_PRICE_DEC,
+  MIN_GAS_LIMIT_DEC,
+  MIN_GAS_PRICE_GWEI,
 } = require('../send/send-constants')
 
-const { conversionUtil, multiplyCurrencies } = require('../../conversion-util')
+const {
+  isBalanceSufficient,
+} = require('../send/send-utils')
+
+const {
+  conversionUtil,
+  multiplyCurrencies,
+  conversionGreaterThan,
+} = require('../../conversion-util')
 
 const {
   getGasPrice,
   getGasLimit,
   conversionRateSelector,
+  getSendAmount,
+  getSelectedToken,
+  getSendFrom,
+  getCurrentAccountWithSendEtherInfo,
+  getSelectedTokenToFiatRate,
 } = require('../../selectors')
 
 function mapStateToProps (state) {
+  const selectedToken = getSelectedToken(state)
+  const currentAccount = getSendFrom(state) || getCurrentAccountWithSendEtherInfo(state)
+  const conversionRate = conversionRateSelector(state)
+
   return {
     gasPrice: getGasPrice(state),
     gasLimit: getGasLimit(state),
-    conversionRate: conversionRateSelector(state),
+    conversionRate,
+    amount: getSendAmount(state),
+    balance: currentAccount.balance,
+    primaryCurrency: selectedToken && selectedToken.symbol,
+    selectedToken,
+    amountConversionRate: selectedToken ? getSelectedTokenToFiatRate(state) : conversionRate,
   }
 }
 
@@ -39,15 +62,26 @@ inherits(CustomizeGasModal, Component)
 function CustomizeGasModal (props) {
   Component.call(this)
 
+  const gasPrice = props.gasPrice || MIN_GAS_PRICE_DEC
+  const gasLimit = props.gasLimit || MIN_GAS_LIMIT_DEC
+
+  const gasTotal = multiplyCurrencies(gasLimit, gasPrice, {
+    toNumericBase: 'hex',
+    multiplicandBase: 16,
+    multiplierBase: 16,
+  })
+
   this.state = {
-    gasPrice: props.gasPrice || MIN_GAS_PRICE,
-    gasLimit: props.gasLimit || MIN_GAS_LIMIT,
+    gasPrice,
+    gasLimit,
+    gasTotal,
+    error: null,
   }
 }
 
 module.exports = connect(mapStateToProps, mapDispatchToProps)(CustomizeGasModal)
 
-CustomizeGasModal.prototype.save = function (gasPrice, gasLimit) {
+CustomizeGasModal.prototype.save = function (gasPrice, gasLimit, gasTotal) {
   const {
     updateGasPrice,
     updateGasLimit,
@@ -55,41 +89,101 @@ CustomizeGasModal.prototype.save = function (gasPrice, gasLimit) {
     updateGasTotal
   } = this.props
 
-  const newGasTotal = multiplyCurrencies(gasLimit, gasPrice, {
+  updateGasPrice(gasPrice)
+  updateGasLimit(gasLimit)
+  updateGasTotal(gasTotal)
+  hideModal()
+}
+
+CustomizeGasModal.prototype.validate = function ({ gasTotal, gasLimit }) {
+  const {
+    amount,
+    balance,
+    primaryCurrency,
+    selectedToken,
+    amountConversionRate,
+    conversionRate,
+  } = this.props
+
+  let error = null
+
+  const balanceIsSufficient = isBalanceSufficient({
+    amount,
+    gasTotal,
+    balance,
+    primaryCurrency,
+    selectedToken,
+    amountConversionRate,
+    conversionRate,
+  })
+
+  if (!balanceIsSufficient) {
+    error = 'Insufficient balance for current gas total' 
+  }
+  
+  const gasLimitTooLow = gasLimit && conversionGreaterThan(
+    {
+      value: MIN_GAS_LIMIT_DEC,
+      fromNumericBase: 'dec',
+      conversionRate,
+    },
+    {
+      value: gasLimit,
+      fromNumericBase: 'hex',
+    },
+  )
+
+  if (gasLimitTooLow) {
+    error = 'Gas limit must be at least 21000' 
+  }
+
+  this.setState({ error })
+  return error
+}
+
+CustomizeGasModal.prototype.convertAndSetGasLimit = function (newGasLimit) {
+  const { gasPrice } = this.state
+
+  const gasLimit = conversionUtil(newGasLimit, {
+    fromNumericBase: 'dec',
+    toNumericBase: 'hex',
+  })
+
+  const gasTotal = multiplyCurrencies(gasLimit, gasPrice, {
     toNumericBase: 'hex',
     multiplicandBase: 16,
     multiplierBase: 16,
   })
 
-  updateGasPrice(gasPrice)
-  updateGasLimit(gasLimit)
-  updateGasTotal(newGasTotal)
-  hideModal()
-}
+  this.validate({ gasTotal, gasLimit })
 
-CustomizeGasModal.prototype.convertAndSetGasLimit = function (newGasLimit) {
-  const convertedGasLimit = conversionUtil(newGasLimit, {
-    fromNumericBase: 'dec',
-    toNumericBase: 'hex',
-  })
-
-  this.setState({ gasLimit: convertedGasLimit })
+  this.setState({ gasTotal, gasLimit })
 }
 
 CustomizeGasModal.prototype.convertAndSetGasPrice = function (newGasPrice) {
-  const convertedGasPrice = conversionUtil(newGasPrice, {
+  const { gasLimit } = this.state
+
+  const gasPrice = conversionUtil(newGasPrice, {
     fromNumericBase: 'dec',
     toNumericBase: 'hex',
     fromDenomination: 'GWEI',
     toDenomination: 'WEI',
   })
 
-  this.setState({ gasPrice: convertedGasPrice })
+  const gasTotal = multiplyCurrencies(gasLimit, gasPrice, {
+    toNumericBase: 'hex',
+    multiplicandBase: 16,
+    multiplierBase: 16,
+  })
+
+  this.validate({ gasTotal })
+
+  this.setState({ gasTotal, gasPrice })
 }
 
 CustomizeGasModal.prototype.render = function () {
   const { hideModal, conversionRate } = this.props
-  const { gasPrice, gasLimit } = this.state
+  const { gasPrice, gasLimit, gasTotal, error } = this.state
 
   const convertedGasPrice = conversionUtil(gasPrice, {
     fromNumericBase: 'hex',
@@ -120,7 +214,7 @@ CustomizeGasModal.prototype.render = function () {
         
         h(GasModalCard, {
           value: convertedGasPrice,
-          min: MIN_GAS_PRICE,
+          min: MIN_GAS_PRICE_GWEI,
           // max: 1000,
           step: 1,
           onChange: value => this.convertAndSetGasPrice(value),
@@ -130,7 +224,7 @@ CustomizeGasModal.prototype.render = function () {
 
         h(GasModalCard, {
           value: convertedGasLimit,
-          min: MIN_GAS_LIMIT,
+          min: 1,
           // max: 100000,
           step: 1,
           onChange: value => this.convertAndSetGasLimit(value),
@@ -141,6 +235,10 @@ CustomizeGasModal.prototype.render = function () {
       ]),
 
       h('div.send-v2__customize-gas__footer', {}, [
+
+        error && h('div.send-v2__customize-gas__error-message', [
+          error,
+        ]),
         
         h('div.send-v2__customize-gas__revert', {
           onClick: () => console.log('Revert'),
@@ -151,8 +249,8 @@ CustomizeGasModal.prototype.render = function () {
             onClick: this.props.hideModal,
           }, ['CANCEL']),
 
-          h('div.send-v2__customize-gas__save', {
-            onClick: () => this.save(gasPrice, gasLimit),
+          h(`div.send-v2__customize-gas__save${error ? '__error' : ''}`, {
+            onClick: () => !error && this.save(gasPrice, gasLimit, gasTotal),
           }, ['SAVE']),
         ])
 
diff --git a/ui/app/components/pending-tx/confirm-send-ether.js b/ui/app/components/pending-tx/confirm-send-ether.js
index 7162c7122..64da630f6 100644
--- a/ui/app/components/pending-tx/confirm-send-ether.js
+++ b/ui/app/components/pending-tx/confirm-send-ether.js
@@ -50,7 +50,7 @@ ConfirmSendEther.prototype.getAmount = function () {
   const { conversionRate, currentCurrency } = this.props
   const txMeta = this.gatherTxMeta()
   const txParams = txMeta.txParams || {}
-  console.log(`conversionRate, currentCurrency`, conversionRate, currentCurrency);
+
   const FIAT = conversionUtil(txParams.value, {
     fromNumericBase: 'hex',
     toNumericBase: 'dec',
diff --git a/ui/app/components/send/send-constants.js b/ui/app/components/send/send-constants.js
index a819a8c28..8b56607cc 100644
--- a/ui/app/components/send/send-constants.js
+++ b/ui/app/components/send/send-constants.js
@@ -3,12 +3,19 @@ const { multiplyCurrencies } = require('../../conversion-util')
 
 const MIN_GAS_PRICE_GWEI = '1'
 const GWEI_FACTOR = '1e9'
-const MIN_GAS_PRICE = multiplyCurrencies(GWEI_FACTOR, MIN_GAS_PRICE_GWEI, {
+const MIN_GAS_PRICE_HEX = multiplyCurrencies(GWEI_FACTOR, MIN_GAS_PRICE_GWEI, {
 	multiplicandBase: 16,
 	multiplierBase: 16,
+  toNumericBase: 'hex',
 })
-const MIN_GAS_LIMIT = (21000).toString(16)
-const MIN_GAS_TOTAL = multiplyCurrencies(MIN_GAS_LIMIT, MIN_GAS_PRICE, {
+const MIN_GAS_PRICE_DEC = multiplyCurrencies(GWEI_FACTOR, MIN_GAS_PRICE_GWEI, {
+  multiplicandBase: 16,
+  multiplierBase: 16,
+  toNumericBase: 'dec',
+})
+const MIN_GAS_LIMIT_HEX = (21000).toString(16)
+const MIN_GAS_LIMIT_DEC = 21000
+const MIN_GAS_TOTAL = multiplyCurrencies(MIN_GAS_LIMIT_HEX, MIN_GAS_PRICE_HEX, {
   toNumericBase: 'hex',
   multiplicandBase: 16,
   multiplierBase: 16,
@@ -16,8 +23,9 @@ const MIN_GAS_TOTAL = multiplyCurrencies(MIN_GAS_LIMIT, MIN_GAS_PRICE, {
 
 module.exports = {
   MIN_GAS_PRICE_GWEI,
-  GWEI_FACTOR,
-  MIN_GAS_PRICE,
-  MIN_GAS_LIMIT,
+  MIN_GAS_PRICE_HEX,
+  MIN_GAS_PRICE_DEC,
+  MIN_GAS_LIMIT_HEX,
+  MIN_GAS_LIMIT_DEC,
   MIN_GAS_TOTAL,
 }
diff --git a/ui/app/components/send/send-utils.js b/ui/app/components/send/send-utils.js
new file mode 100644
index 000000000..bf096d610
--- /dev/null
+++ b/ui/app/components/send/send-utils.js
@@ -0,0 +1,39 @@
+const { addCurrencies, conversionGreaterThan } = require('../../conversion-util')
+
+function isBalanceSufficient({
+  amount,
+  gasTotal,
+  balance,
+  primaryCurrency,
+  selectedToken,
+  amountConversionRate,
+  conversionRate,
+}) {
+  const totalAmount = addCurrencies(amount, gasTotal, {
+    aBase: 16,
+    bBase: 16,
+    toNumericBase: 'hex',
+  })
+
+  const balanceIsSufficient = conversionGreaterThan(
+    {
+      value: balance,
+      fromNumericBase: 'hex',
+      fromCurrency: primaryCurrency,
+      conversionRate,
+    },
+    {
+      value: totalAmount,
+      fromNumericBase: 'hex',
+      conversionRate: amountConversionRate,
+      fromCurrency: selectedToken || primaryCurrency,
+      conversionRate: amountConversionRate,
+    },
+  )
+
+  return balanceIsSufficient
+}
+
+module.exports = {
+  isBalanceSufficient,
+}
\ No newline at end of file
diff --git a/ui/app/components/send/send-v2-container.js b/ui/app/components/send/send-v2-container.js
index 80b52a3ab..fb2634de2 100644
--- a/ui/app/components/send/send-v2-container.js
+++ b/ui/app/components/send/send-v2-container.js
@@ -17,6 +17,7 @@ const {
   getAddressBook,
   getSendFrom,
   getCurrentCurrency,
+  getSelectedTokenToFiatRate,
 } = require('../../selectors')
 
 module.exports = connect(mapStateToProps, mapDispatchToProps)(SendEther)
@@ -26,7 +27,6 @@ function mapStateToProps (state) {
   const selectedAddress = getSelectedAddress(state)
   const selectedToken = getSelectedToken(state)
   const tokenExchangeRates = state.metamask.tokenExchangeRates
-  const selectedTokenExchangeRate = getSelectedTokenExchangeRate(state)
   const conversionRate = conversionRateSelector(state)
 
   let data;
@@ -40,11 +40,7 @@ function mapStateToProps (state) {
 
     primaryCurrency = selectedToken.symbol
 
-    tokenToFiatRate = multiplyCurrencies(
-      conversionRate,
-      selectedTokenExchangeRate,
-      { toNumericBase: 'dec' }
-    )
+    tokenToFiatRate = getSelectedTokenToFiatRate(state)
   }
 
   return {
diff --git a/ui/app/css/itcss/components/send.scss b/ui/app/css/itcss/components/send.scss
index c4efeccf0..d2415f26c 100644
--- a/ui/app/css/itcss/components/send.scss
+++ b/ui/app/css/itcss/components/send.scss
@@ -738,6 +738,7 @@
       align-items: center;
       justify-content: space-between;
       font-size: 22px;
+      position: relative;
     }
 
     &__buttons {
@@ -747,7 +748,7 @@
       margin-right: 21.25px;
     }
 
-    &__revert, &__cancel, &__save {
+    &__revert, &__cancel, &__save, &__save__error {
       display: flex;
       justify-content: center;
       align-items: center;
@@ -760,7 +761,7 @@
       margin-left: 21.25px;
     }
 
-    &__cancel, &__save {
+    &__cancel, &__save, &__save__error {
       height: 34.64px;
       width: 85.74px;
       border: 1px solid $dusty-gray;
@@ -769,6 +770,21 @@
       font-size: 12px;
       color: $dusty-gray;
     }
+
+    &__save__error {
+      opacity: 0.5;
+      cursor: auto;
+    }
+
+    &__error-message {
+      display: block;
+      position: absolute;
+      top: 4px;
+      right: 4px;
+      font-size: 12px;
+      line-height: 12px;
+      color: $red;
+    }
   }
 
   &__gas-modal-card {
diff --git a/ui/app/selectors.js b/ui/app/selectors.js
index 4c3d21d33..3a15cef4c 100644
--- a/ui/app/selectors.js
+++ b/ui/app/selectors.js
@@ -1,5 +1,9 @@
 const valuesFor = require('./util').valuesFor
 
+const {
+  multiplyCurrencies,
+} = require('./conversion-util')
+
 const selectors = {
   getSelectedAddress,
   getSelectedIdentity,
@@ -16,6 +20,8 @@ const selectors = {
   getAddressBook,
   getSendFrom,
   getCurrentCurrency,
+  getSendAmount,
+  getSelectedTokenToFiatRate,
 }
 
 module.exports = selectors
@@ -123,6 +129,23 @@ function getSendFrom (state) {
   return state.metamask.send.from
 }
 
+function getSendAmount (state) {
+  return state.metamask.send.amount
+}
+
 function getCurrentCurrency (state) {
   return state.metamask.currentCurrency
 }
+
+function getSelectedTokenToFiatRate (state) {
+  const selectedTokenExchangeRate = getSelectedTokenExchangeRate(state)
+  const conversionRate = conversionRateSelector(state)
+
+  const tokenToFiatRate = multiplyCurrencies(
+    conversionRate,
+    selectedTokenExchangeRate,
+    { toNumericBase: 'dec' }
+  )
+
+  return tokenToFiatRate
+}
diff --git a/ui/app/send-v2.js b/ui/app/send-v2.js
index 4986edf5f..16e4d7801 100644
--- a/ui/app/send-v2.js
+++ b/ui/app/send-v2.js
@@ -19,6 +19,9 @@ const {
   conversionGreaterThan,
   addCurrencies,
 } = require('./conversion-util')
+const {
+  isBalanceSufficient,
+} = require('./components/send/send-utils.js')
 const { isValidAddress } = require('./util')
 
 module.exports = SendTransactionScreen
@@ -237,28 +240,16 @@ SendTransactionScreen.prototype.validateAmount = function (value) {
 
   let amountError = null
 
-  const totalAmount = addCurrencies(amount, gasTotal, {
-    aBase: 16,
-    bBase: 16,
-    toNumericBase: 'hex',
+  const sufficientBalance = isBalanceSufficient({
+    amount,
+    gasTotal,
+    balance,
+    primaryCurrency,
+    selectedToken,
+    amountConversionRate,
+    conversionRate,
   })
 
-  const sufficientBalance = conversionGreaterThan(
-    {
-      value: balance,
-      fromNumericBase: 'hex',
-      fromCurrency: primaryCurrency,
-      conversionRate,
-    },
-    {
-      value: totalAmount,
-      fromNumericBase: 'hex',
-      conversionRate: amountConversionRate,
-      fromCurrency: selectedToken || primaryCurrency,
-      conversionRate: amountConversionRate,
-    },
-  )
-
   const amountLessThanZero = conversionGreaterThan(
     { value: 0, fromNumericBase: 'dec' },
     { value: amount, fromNumericBase: 'hex' },
@@ -387,7 +378,7 @@ SendTransactionScreen.prototype.renderFooter = function () {
     clearSend,
     errors: { amount: amountError, to: toError }
   } = this.props
-  
+
   const noErrors = amountError === null && toError === null
   const errorClass = noErrors ? '' : '__disabled'