diff --git a/ui/app/components/send_/tests/send-selectors-test-data.js b/ui/app/components/send_/tests/send-selectors-test-data.js
index 1a95b5f41..ecfe9022f 100644
--- a/ui/app/components/send_/tests/send-selectors-test-data.js
+++ b/ui/app/components/send_/tests/send-selectors-test-data.js
@@ -90,31 +90,31 @@ module.exports = {
       {
         'id': 'mockTokenTx1',
         'txParams': {
-          'to': '0x8d6b81208414189a58339873ab429b6c47ab92d3'
+          'to': '0x8d6b81208414189a58339873ab429b6c47ab92d3',
         },
-        'time': 1700000000000
+        'time': 1700000000000,
       },
       {
         'id': 'mockTokenTx2',
         'txParams': {
-          'to': '0xafaketokenaddress'
+          'to': '0xafaketokenaddress',
         },
-        'time': 1600000000000
+        'time': 1600000000000,
       },
       {
         'id': 'mockTokenTx3',
         'txParams': {
-          'to': '0x8d6b81208414189a58339873ab429b6c47ab92d3'
+          'to': '0x8d6b81208414189a58339873ab429b6c47ab92d3',
         },
-        'time': 1500000000000
+        'time': 1500000000000,
       },
       {
         'id': 'mockEthTx1',
         'txParams': {
-          'to': '0xd85a4b6a394794842887b8284293d69163007bbb'
+          'to': '0xd85a4b6a394794842887b8284293d69163007bbb',
         },
-        'time': 1400000000000
-      }
+        'time': 1400000000000,
+      },
     ],
     'selectedTokenAddress': '0x8d6b81208414189a58339873ab429b6c47ab92d3',
     'unapprovedMsgs': {
@@ -195,7 +195,7 @@ module.exports = {
         'txValue': 'de0b6b3a7640000',
         'maxCost': 'de234b52e4a0800',
         'gasPrice': '4a817c800',
-      }
+      },
     },
     'currentLocale': 'en',
   },
diff --git a/ui/app/components/send_/tests/send-selectors.test.js b/ui/app/components/send_/tests/send-selectors.test.js
index e2acc15f6..9dc207ead 100644
--- a/ui/app/components/send_/tests/send-selectors.test.js
+++ b/ui/app/components/send_/tests/send-selectors.test.js
@@ -42,12 +42,12 @@ const {
 import mockState from './send-selectors-test-data'
 
 describe('send selectors', () => {
-  let tempGlobalEth = Object.assign({}, global.eth)
+  const tempGlobalEth = Object.assign({}, global.eth)
   beforeEach(() => {
     global.eth = {
       contract: sinon.stub().returns({
-        at: address => 'mockAt:' + address
-      })
+        at: address => 'mockAt:' + address,
+      }),
     }
   })
 
diff --git a/ui/app/ducks/send.duck.js b/ui/app/ducks/send.duck.js
index aef493ea0..055cc05c1 100644
--- a/ui/app/ducks/send.duck.js
+++ b/ui/app/ducks/send.duck.js
@@ -16,32 +16,34 @@ const initState = {
 
 // Reducer
 export default function reducer ({ send: sendState = initState }, action = {}) {
+  const newState = extend({}, sendState)
+
   switch (action.type) {
     case OPEN_FROM_DROPDOWN:
-      return extend(sendState, {
+      return extend(newState, {
         fromDropdownOpen: true,
       })
     case CLOSE_FROM_DROPDOWN:
-      return extend(sendState, {
+      return extend(newState, {
         fromDropdownOpen: false,
       })
     case OPEN_TO_DROPDOWN:
-      return extend(sendState, {
+      return extend(newState, {
         toDropdownOpen: true,
       })
     case CLOSE_TO_DROPDOWN:
-      return extend(sendState, {
+      return extend(newState, {
         toDropdownOpen: false,
       })
     case UPDATE_SEND_ERRORS:
-      return extend(sendState, {
+      return extend(newState, {
         errors: {
-          ...sendState.errors,
+          ...newState.errors,
           ...action.value,
         },
       })
     default:
-      return sendState
+      return newState
   }
 }
 
diff --git a/ui/app/ducks/tests/send-duck.test.js b/ui/app/ducks/tests/send-duck.test.js
new file mode 100644
index 000000000..c06cf55d2
--- /dev/null
+++ b/ui/app/ducks/tests/send-duck.test.js
@@ -0,0 +1,145 @@
+import assert from 'assert'
+
+import SendReducer, {
+  openFromDropdown,
+  closeFromDropdown,
+  openToDropdown,
+  closeToDropdown,
+  updateSendErrors,
+} from '../send.duck.js'
+
+describe('Send Duck', () => {
+  const mockState = {
+    send: {
+      mockProp: 123,
+    },
+  }
+  const initState = {
+    fromDropdownOpen: false,
+    toDropdownOpen: false,
+    errors: {},
+  }
+  const OPEN_FROM_DROPDOWN = 'metamask/send/OPEN_FROM_DROPDOWN'
+  const CLOSE_FROM_DROPDOWN = 'metamask/send/CLOSE_FROM_DROPDOWN'
+  const OPEN_TO_DROPDOWN = 'metamask/send/OPEN_TO_DROPDOWN'
+  const CLOSE_TO_DROPDOWN = 'metamask/send/CLOSE_TO_DROPDOWN'
+  const UPDATE_SEND_ERRORS = 'metamask/send/UPDATE_SEND_ERRORS'
+
+  describe('SendReducer()', () => {
+    it('should initialize state', () => {
+      assert.deepEqual(
+        SendReducer({}),
+        initState
+      )
+    })
+
+    it('should return state unchanged if it does not match a dispatched actions type', () => {
+      assert.deepEqual(
+        SendReducer(mockState, {
+          type: 'someOtherAction',
+          value: 'someValue',
+        }),
+        Object.assign({}, mockState.send)
+      )
+    })
+
+    it('should set fromDropdownOpen to true when receiving a OPEN_FROM_DROPDOWN action', () => {
+      assert.deepEqual(
+        SendReducer(mockState, {
+          type: OPEN_FROM_DROPDOWN,
+        }),
+        Object.assign({fromDropdownOpen: true}, mockState.send)
+      )
+    })
+
+    it('should return a new object (and not just modify the existing state object)', () => {
+      assert.deepEqual(SendReducer(mockState), mockState.send)
+      assert.notEqual(SendReducer(mockState), mockState.send)
+    })
+
+    it('should set fromDropdownOpen to false when receiving a CLOSE_FROM_DROPDOWN action', () => {
+      assert.deepEqual(
+        SendReducer(mockState, {
+          type: CLOSE_FROM_DROPDOWN,
+        }),
+        Object.assign({fromDropdownOpen: false}, mockState.send)
+      )
+    })
+
+    it('should set toDropdownOpen to true when receiving a OPEN_TO_DROPDOWN action', () => {
+      assert.deepEqual(
+        SendReducer(mockState, {
+          type: OPEN_TO_DROPDOWN,
+        }),
+        Object.assign({toDropdownOpen: true}, mockState.send)
+      )
+    })
+
+    it('should set toDropdownOpen to false when receiving a CLOSE_TO_DROPDOWN action', () => {
+      assert.deepEqual(
+        SendReducer(mockState, {
+          type: CLOSE_TO_DROPDOWN,
+        }),
+        Object.assign({toDropdownOpen: false}, mockState.send)
+      )
+    })
+
+    it('should extend send.errors with the value of a UPDATE_SEND_ERRORS action', () => {
+      const modifiedMockState = Object.assign({}, mockState, {
+        send: {
+          errors: {
+            someError: false,
+          },
+        },
+      })
+      assert.deepEqual(
+        SendReducer(modifiedMockState, {
+          type: UPDATE_SEND_ERRORS,
+          value: { someOtherError: true },
+        }),
+        Object.assign({}, modifiedMockState.send, {
+          errors: {
+            someError: false,
+            someOtherError: true,
+          },
+        })
+      )
+    })
+  })
+
+  describe('openFromDropdown', () => {
+    assert.deepEqual(
+      openFromDropdown(),
+      { type: OPEN_FROM_DROPDOWN }
+    )
+  })
+
+  describe('closeFromDropdown', () => {
+    assert.deepEqual(
+      closeFromDropdown(),
+      { type: CLOSE_FROM_DROPDOWN }
+    )
+  })
+
+  describe('openToDropdown', () => {
+    assert.deepEqual(
+      openToDropdown(),
+      { type: OPEN_TO_DROPDOWN }
+    )
+  })
+
+  describe('closeToDropdown', () => {
+    assert.deepEqual(
+      closeToDropdown(),
+      { type: CLOSE_TO_DROPDOWN }
+    )
+  })
+
+  describe('updateSendErrors', () => {
+    assert.deepEqual(
+      updateSendErrors('mockErrorObject'),
+      { type: UPDATE_SEND_ERRORS, value: 'mockErrorObject' }
+    )
+  })
+
+})