diff --git a/app/internal_packages/composer/lib/composer-header.jsx b/app/internal_packages/composer/lib/composer-header.jsx
index 3cdec195e..2ac0c83b7 100644
--- a/app/internal_packages/composer/lib/composer-header.jsx
+++ b/app/internal_packages/composer/lib/composer-header.jsx
@@ -127,7 +127,7 @@ export default class ComposerHeader extends React.Component {
     if (DraftHelpers.isForwardedMessage(this.props.draft)) {
       return true;
     }
-    if (this.props.draft.replyToMessageId) {
+    if (this.props.draft.replyToHeaderMessageId) {
       return false;
     }
     return true;
diff --git a/app/internal_packages/composer/specs/composer-header-spec.jsx b/app/internal_packages/composer/specs/composer-header-spec.jsx
index 2e3acab2a..8189f7f07 100644
--- a/app/internal_packages/composer/specs/composer-header-spec.jsx
+++ b/app/internal_packages/composer/specs/composer-header-spec.jsx
@@ -111,7 +111,7 @@ describe('ComposerHeader', function composerHeader() {
       });
 
       it("should be hidden if the message is a reply", () => {
-        const draft = new Message({draft: true, subject: 'Re: 1234', replyToMessageId: '123', accountId: TEST_ACCOUNT_ID, headerMessageId: DRAFT_HEADER_MSG_ID});
+        const draft = new Message({draft: true, subject: 'Re: 1234', replyToHeaderMessageId: '123', accountId: TEST_ACCOUNT_ID, headerMessageId: DRAFT_HEADER_MSG_ID});
         this.createWithDraft(draft);
         expect(this.component.state.enabledFields).toEqual(['textFieldTo', 'fromField'])
       });
diff --git a/app/internal_packages/composer/specs/composer-view-spec.cjsx b/app/internal_packages/composer/specs/composer-view-spec.cjsx
index 0e2ebd656..5176921d9 100644
--- a/app/internal_packages/composer/specs/composer-view-spec.cjsx
+++ b/app/internal_packages/composer/specs/composer-view-spec.cjsx
@@ -62,7 +62,7 @@ useFullDraft = ->
     files: [f1, f2]
     subject: "Test Message 1"
     body: "Hello <b>World</b><br/> This is a test"
-    replyToMessageId: null
+    replyToHeaderMessageId: null
 
 makeComposer = (props={}) ->
   @composer = NylasTestUtils.renderIntoDocument(
@@ -118,7 +118,7 @@ describe "ComposerView", ->
         to: [u2]
         subject: "Test Reply Message 1"
         body: ""
-        replyToMessageId: "1")
+        replyToHeaderMessageId: "1")
       .then( =>
         sessionSetupComplete = true
       )
diff --git a/app/internal_packages/draft-list/lib/draft-list-store.coffee b/app/internal_packages/draft-list/lib/draft-list-store.coffee
index 883e84330..d78169ffe 100644
--- a/app/internal_packages/draft-list/lib/draft-list-store.coffee
+++ b/app/internal_packages/draft-list/lib/draft-list-store.coffee
@@ -56,6 +56,7 @@ class DraftListStore extends NylasStore
         # where we set thread.__messages to the message array.
         resultSetWithTasks = new MutableQueryResultSet(resultSet)
 
+        # TODO BG modelWithId: task.headerMessageId does not work
         mailboxPerspective.accountIds.forEach (aid) =>
           OutboxStore.itemsForAccount(aid).forEach (task) =>
             draft = resultSet.modelWithId(task.headerMessageId)
diff --git a/app/spec/stores/draft-factory-spec.es6 b/app/spec/stores/draft-factory-spec.es6
index 8f089400a..e26bfaa44 100644
--- a/app/spec/stores/draft-factory-spec.es6
+++ b/app/spec/stores/draft-factory-spec.es6
@@ -60,6 +60,7 @@ describe('DraftFactory', function draftFactory() {
 
     fakeMessage1 = new Message({
       id: 'fake-message-1',
+      headerMessageId: 'fake-message-1@localhost',
       accountId: account.id,
       to: [new Contact({email: 'ben@nylas.com'}), new Contact({email: 'evan@nylas.com'})],
       cc: [new Contact({email: 'mg@nylas.com'}), account.me()],
@@ -73,6 +74,7 @@ describe('DraftFactory', function draftFactory() {
 
     fakeMessageWithFiles = new Message({
       id: 'fake-message-with-files',
+      headerMessageId: 'fake-message-with-files@localhost',
       accountId: account.id,
       to: [new Contact({email: 'ben@nylas.com'}), new Contact({email: 'evan@nylas.com'})],
       cc: [new Contact({email: 'mg@nylas.com'}), account.me()],
@@ -87,6 +89,7 @@ describe('DraftFactory', function draftFactory() {
 
     msgFromMe = new Message({
       id: 'fake-message-3',
+      headerMessageId: 'fake-message-3@localhost',
       accountId: account.id,
       to: [new Contact({email: '1@1.com'}), new Contact({email: '2@2.com'})],
       cc: [new Contact({email: '3@3.com'}), new Contact({email: '4@4.com'})],
@@ -100,6 +103,7 @@ describe('DraftFactory', function draftFactory() {
 
     msgWithReplyTo = new Message({
       id: 'fake-message-reply-to',
+      headerMessageId: 'fake-message-reply-to@localhost',
       accountId: account.id,
       to: [new Contact({email: '1@1.com'}), new Contact({email: '2@2.com'})],
       cc: [new Contact({email: '3@3.com'}), new Contact({email: '4@4.com'})],
@@ -122,6 +126,7 @@ describe('DraftFactory', function draftFactory() {
 
     msgWithReplyToDuplicates = new Message({
       id: 'fake-message-reply-to-duplicates',
+      headerMessageId: 'fake-message-reply-to-duplicates@localhost',
       accountId: account.id,
       to: [new Contact({email: '1@1.com'}), new Contact({email: '2@2.com'})],
       cc: [new Contact({email: '1@1.com'}), new Contact({email: '4@4.com'})],
@@ -152,10 +157,10 @@ describe('DraftFactory', function draftFactory() {
         });
       });
 
-      it("should set the replyToMessageId to the previous message's ids", () => {
+      it("should set the replyToHeaderMessageId to the previous message's ids", () => {
         waitsForPromise(() => {
           return DraftFactory.createDraftForReply({thread: fakeThread, message: fakeMessage1, type: 'reply'}).then((draft) => {
-            expect(draft.replyToMessageId).toEqual(fakeMessage1.id);
+            expect(draft.replyToHeaderMessageId).toEqual(fakeMessage1.headerMessageId);
           });
         });
       });
@@ -378,8 +383,8 @@ describe('DraftFactory', function draftFactory() {
         expect(this.model.bcc).toEqual([]);
       });
 
-      it("should not set the replyToMessageId", () => {
-        expect(this.model.replyToMessageId).toEqual(undefined);
+      it("should not set the replyToHeaderMessageId", () => {
+        expect(this.model.replyToHeaderMessageId).toEqual(undefined);
       });
 
       it("should sanitize the HTML", () => {
@@ -433,7 +438,7 @@ describe('DraftFactory', function draftFactory() {
         this.existingDraft = new Message({
           id: 'asd',
           accountId: TEST_ACCOUNT_ID,
-          replyToMessageId: fakeMessage1.id,
+          replyToHeaderMessageId: fakeMessage1.headerMessageId,
           threadId: fakeMessage1.threadId,
           draft: true,
         });
diff --git a/app/spec/stores/draft-helpers-spec.es6 b/app/spec/stores/draft-helpers-spec.es6
index ced90b832..6d9b217ad 100644
--- a/app/spec/stores/draft-helpers-spec.es6
+++ b/app/spec/stores/draft-helpers-spec.es6
@@ -54,7 +54,7 @@ xdescribe('DraftHelpers', function describeBlock() {
   describe('shouldAppendQuotedText', () => {
     it('returns true if message is reply and has no marker', () => {
       const draft = {
-        replyToMessageId: 1,
+        replyToHeaderMessageId: 1,
         body: `<div>hello!</div>`,
       }
       expect(DraftHelpers.shouldAppendQuotedText(draft)).toBe(true)
@@ -62,7 +62,7 @@ xdescribe('DraftHelpers', function describeBlock() {
 
     it('returns false if message is reply and has marker', () => {
       const draft = {
-        replyToMessageId: 1,
+        replyToHeaderMessageId: 1,
         body: `<div>hello!</div><div id="n1-quoted-text-marker"></div>Quoted Text`,
       }
       expect(DraftHelpers.shouldAppendQuotedText(draft)).toBe(false)
diff --git a/app/spec/stores/draft-store-spec.es6 b/app/spec/stores/draft-store-spec.es6
index 5e657368d..8de08303b 100644
--- a/app/spec/stores/draft-store-spec.es6
+++ b/app/spec/stores/draft-store-spec.es6
@@ -302,7 +302,7 @@ xdescribe('DraftStore', function draftStore() {
       this.draft = new Message({
         headerMessageId: "local-123",
         threadId: "thread-123",
-        replyToMessageId: "message-123",
+        replyToHeaderMessageId: "message-123@localhost",
         files: ['stub'],
       });
       DraftStore._draftSessions = {};
diff --git a/app/spec_disabled/tasks/send-draft-task-spec.es6 b/app/spec_disabled/tasks/send-draft-task-spec.es6
index 7d566e8f0..872108712 100644
--- a/app/spec_disabled/tasks/send-draft-task-spec.es6
+++ b/app/spec_disabled/tasks/send-draft-task-spec.es6
@@ -205,7 +205,7 @@ xdescribe('SendDraftTask', function sendDraftTask() {
             return Promise.resolve(this.response);
           });
 
-          this.draft.replyToMessageId = "reply-123";
+          this.draft.replyToHeaderMessageId = "reply-123";
           this.draft.threadId = "thread-123";
           waitsForPromise(() => {
             return this.task.performRemote(this.draft)
@@ -232,7 +232,7 @@ xdescribe('SendDraftTask', function sendDraftTask() {
             return Promise.resolve(this.response);
           });
 
-          this.draft.replyToMessageId = "reply-123";
+          this.draft.replyToHeaderMessageId = "reply-123";
           this.draft.threadId = "thread-123";
           waitsForPromise(() => this.task.performRemote(this.draft).then(() => {
             expect(NylasAPIRequest.prototype.run).toHaveBeenCalled();
diff --git a/app/src/flux/models/message.es6 b/app/src/flux/models/message.es6
index 0d10ab889..1a57661f6 100644
--- a/app/src/flux/models/message.es6
+++ b/app/src/flux/models/message.es6
@@ -56,8 +56,7 @@ All messages are part of a thread, even if that thread has only one message.
 
 `threadId`: {AttributeString} The ID of the Message's parent {Thread}. Queryable.
 
-`replyToMessageId`: {AttributeString} The ID of a {Message} that this message
- === in reply to.
+`replyToHeaderMessageId`: {AttributeString} The headerMessageID of a {Message} that this message is in reply to.
 
 This class also inherits attributes from {Model}
 
@@ -156,8 +155,9 @@ export default class Message extends ModelWithMetadata {
       queryable: true,
     }),
 
-    replyToMessageId: Attributes.String({
-      modelKey: 'replyToMessageId',
+    replyToHeaderMessageId: Attributes.String({
+      jsonKey: 'rthMsgId',
+      modelKey: 'replyToHeaderMessageId',
     }),
 
     folder: Attributes.Object({
diff --git a/app/src/flux/stores/draft-factory.coffee b/app/src/flux/stores/draft-factory.coffee
index 27ea8530f..7f7306ca2 100644
--- a/app/src/flux/stores/draft-factory.coffee
+++ b/app/src/flux/stores/draft-factory.coffee
@@ -120,8 +120,8 @@ class DraftFactory
       from: [@_fromContactForReply(message)],
       threadId: thread.id,
       accountId: message.accountId,
-      replyToMessageId: message.id,
-      body: "" # quoted html is managed by the composer via the replyToMessageId
+      replyToHeaderMessageId: message.headerMessageId,
+      body: "" # quoted html is managed by the composer via the replyToHeaderMessageId
     )
 
   createDraftForForward: ({thread, message}) =>
@@ -166,7 +166,7 @@ class DraftFactory
 
     getMessages.then (messages) =>
       candidateDrafts = messages.filter (other) =>
-        other.replyToMessageId is message.id and other.draft is true
+        other.replyToHeaderMessageId is message.id and other.draft is true
 
       if candidateDrafts.length is 0
         return Promise.resolve(null)
diff --git a/app/src/flux/stores/draft-helpers.es6 b/app/src/flux/stores/draft-helpers.es6
index 1088d6376..20050ba96 100644
--- a/app/src/flux/stores/draft-helpers.es6
+++ b/app/src/flux/stores/draft-helpers.es6
@@ -37,10 +37,10 @@ class DraftHelpers {
     return bodyForwarded || bodyFwd || subjectFwd
   }
 
-  shouldAppendQuotedText({body = '', replyToMessageId = false} = {}) {
-    return replyToMessageId &&
+  shouldAppendQuotedText({body = '', replyToHeaderMessageId = false} = {}) {
+    return replyToHeaderMessageId &&
       !body.includes('<div id="n1-quoted-text-marker">') &&
-      !body.includes(`nylas-quote-id-${replyToMessageId}`)
+      !body.includes(`nylas-quote-id-${replyToHeaderMessageId}`)
   }
 
   prepareBodyForQuoting(body = "") {
@@ -75,7 +75,10 @@ class DraftHelpers {
   }
 
   appendQuotedTextToDraft(draft) {
-    const query = DatabaseStore.find(Message, draft.replyToMessageId).include(Message.attributes.body);
+    const query = DatabaseStore.findBy(Message, {
+      headerMessageId: draft.replyToHeaderMessageId,
+      accountId: draft.accountId,
+    }).include(Message.attributes.body);
 
     return query.then((prevMessage) => {
       if (!prevMessage) {
@@ -83,7 +86,7 @@ class DraftHelpers {
       }
       return this.prepareBodyForQuoting(prevMessage.body).then((prevBodySanitized) => {
         draft.body = `${draft.body}
-          <div class="gmail_quote nylas-quote nylas-quote-id-${draft.replyToMessageId}">
+          <div class="gmail_quote nylas-quote nylas-quote-id-${draft.replyToHeaderMessageId}">
             <br>
             ${DOMUtils.escapeHTMLCharacters(prevMessage.replyAttributionLine())}
             <br>
@@ -127,7 +130,7 @@ class DraftHelpers {
 
     draft = await this.applyExtensionTransforms(draft)
     draft = await this.pruneRemovedInlineFiles(draft);
-    if (draft.replyToMessageId && this.shouldAppendQuotedText(draft)) {
+    if (draft.replyToHeaderMessageId && this.shouldAppendQuotedText(draft)) {
       draft = await this.appendQuotedTextToDraft(draft);
     }
     return draft;
diff --git a/app/src/flux/stores/message-store.coffee b/app/src/flux/stores/message-store.coffee
index 71fef22a3..497ff74b4 100644
--- a/app/src/flux/stores/message-store.coffee
+++ b/app/src/flux/stores/message-store.coffee
@@ -280,10 +280,10 @@ class MessageStore extends NylasStore
   _sortItemsForDisplay: (items) ->
     # Re-sort items in the list so that drafts appear after the message that
     # they are in reply to, when possible. First, identify all the drafts
-    # with a replyToMessageId and remove them
+    # with a replyToHeaderMessageId and remove them
     itemsInReplyTo = []
     for item, index in items by -1
-      if item.draft and item.replyToMessageId
+      if item.draft and item.replyToHeaderMessageId
         itemsInReplyTo.push(item)
         items.splice(index, 1)
 
@@ -291,7 +291,7 @@ class MessageStore extends NylasStore
     # the message which it was in reply to. If we can't find it, put it at the end.
     for item in itemsInReplyTo
       for other, index in items
-        if item.replyToMessageId is other.id
+        if item.replyToHeaderMessageId is other.id
           items.splice(index+1, 0, item)
           item = null
           break