diff --git a/src/autocomplete/CommunityProvider.js b/src/autocomplete/CommunityProvider.js
index ffce1e71cf..992df0f773 100644
--- a/src/autocomplete/CommunityProvider.js
+++ b/src/autocomplete/CommunityProvider.js
@@ -105,8 +105,14 @@ export default class CommunityProvider extends AutocompleteProvider {
     }
 
     renderCompletions(completions: [React.Component]): ?React.Component {
-        return <div className="mx_Autocomplete_Completion_container_pill mx_Autocomplete_Completion_container_truncate">
-            { completions }
-        </div>;
+        return (
+            <div
+                className="mx_Autocomplete_Completion_container_pill mx_Autocomplete_Completion_container_truncate"
+                role="listbox"
+                aria-label={_t("Community Autocomplete")}
+            >
+                { completions }
+            </div>
+        );
     }
 }
diff --git a/src/autocomplete/Components.js b/src/autocomplete/Components.js
index b09f4e963e..ca105bb211 100644
--- a/src/autocomplete/Components.js
+++ b/src/autocomplete/Components.js
@@ -60,7 +60,7 @@ export class PillCompletion extends React.Component {
             ...restProps
         } = this.props;
         return (
-            <div className={classNames('mx_Autocomplete_Completion_pill', className)} {...restProps}>
+            <div className={classNames('mx_Autocomplete_Completion_pill', className)} role="option" {...restProps}>
                 { initialComponent }
                 <span className="mx_Autocomplete_Completion_title">{ title }</span>
                 <span className="mx_Autocomplete_Completion_subtitle">{ subtitle }</span>
diff --git a/src/autocomplete/EmojiProvider.js b/src/autocomplete/EmojiProvider.js
index 8afcba6ab0..1e39593022 100644
--- a/src/autocomplete/EmojiProvider.js
+++ b/src/autocomplete/EmojiProvider.js
@@ -116,7 +116,9 @@ export default class EmojiProvider extends AutocompleteProvider {
                 return {
                     completion: unicode,
                     component: (
-                        <PillCompletion title={shortname} initialComponent={<span style={{maxWidth: '1em'}}>{ unicode }</span>} />
+                        <PillCompletion title={shortname} aria-label={unicode} initialComponent={
+                            <span style={{maxWidth: '1em'}}>{ unicode }</span>
+                        } />
                     ),
                     range,
                 };
@@ -130,8 +132,10 @@ export default class EmojiProvider extends AutocompleteProvider {
     }
 
     renderCompletions(completions: [React.Component]): ?React.Component {
-        return <div className="mx_Autocomplete_Completion_container_pill">
-            { completions }
-        </div>;
+        return (
+            <div className="mx_Autocomplete_Completion_container_pill" role="listbox" aria-label={_t("Emoji Autocomplete")}>
+                { completions }
+            </div>
+        );
     }
 }
diff --git a/src/autocomplete/NotifProvider.js b/src/autocomplete/NotifProvider.js
index 60a3352f9b..95cfb34616 100644
--- a/src/autocomplete/NotifProvider.js
+++ b/src/autocomplete/NotifProvider.js
@@ -58,8 +58,14 @@ export default class NotifProvider extends AutocompleteProvider {
     }
 
     renderCompletions(completions: [React.Component]): ?React.Component {
-        return <div className="mx_Autocomplete_Completion_container_pill mx_Autocomplete_Completion_container_truncate">
-            { completions }
-        </div>;
+        return (
+            <div
+                className="mx_Autocomplete_Completion_container_pill mx_Autocomplete_Completion_container_truncate"
+                role="listbox"
+                aria-label={_t("Notification Autocomplete")}
+            >
+                { completions }
+            </div>
+        );
     }
 }
diff --git a/src/autocomplete/RoomProvider.js b/src/autocomplete/RoomProvider.js
index b94edf590c..79986657b8 100644
--- a/src/autocomplete/RoomProvider.js
+++ b/src/autocomplete/RoomProvider.js
@@ -109,8 +109,14 @@ export default class RoomProvider extends AutocompleteProvider {
     }
 
     renderCompletions(completions: [React.Component]): ?React.Component {
-        return <div className="mx_Autocomplete_Completion_container_pill mx_Autocomplete_Completion_container_truncate">
-            { completions }
-        </div>;
+        return (
+            <div
+                className="mx_Autocomplete_Completion_container_pill mx_Autocomplete_Completion_container_truncate"
+                role="listbox"
+                aria-label={_t("Room Autocomplete")}
+            >
+                { completions }
+            </div>
+        );
     }
 }
diff --git a/src/autocomplete/UserProvider.js b/src/autocomplete/UserProvider.js
index 62ae5d4970..451ae0bb83 100644
--- a/src/autocomplete/UserProvider.js
+++ b/src/autocomplete/UserProvider.js
@@ -164,9 +164,11 @@ export default class UserProvider extends AutocompleteProvider {
     }
 
     renderCompletions(completions: [React.Component]): ?React.Component {
-        return <div className="mx_Autocomplete_Completion_container_pill">
-            { completions }
-        </div>;
+        return (
+            <div className="mx_Autocomplete_Completion_container_pill" role="listbox" aria-label={_t("User Autocomplete")}>
+                { completions }
+            </div>
+        );
     }
 
     shouldForceComplete(): boolean {
diff --git a/src/components/views/rooms/Autocomplete.js b/src/components/views/rooms/Autocomplete.js
index 243cfe2f75..ad5fa198a3 100644
--- a/src/components/views/rooms/Autocomplete.js
+++ b/src/components/views/rooms/Autocomplete.js
@@ -20,18 +20,17 @@ import ReactDOM from 'react-dom';
 import PropTypes from 'prop-types';
 import classNames from 'classnames';
 import flatMap from 'lodash/flatMap';
-import isEqual from 'lodash/isEqual';
-import sdk from '../../../index';
 import type {Completion} from '../../../autocomplete/Autocompleter';
 import Promise from 'bluebird';
 import { Room } from 'matrix-js-sdk';
 
-import {getCompletions} from '../../../autocomplete/Autocompleter';
 import SettingsStore from "../../../settings/SettingsStore";
 import Autocompleter from '../../../autocomplete/Autocompleter';
 
 const COMPOSER_SELECTED = 0;
 
+export const generateCompletionDomId = (number) => `mx_Autocomplete_Completion_${number}`;
+
 export default class Autocomplete extends React.Component {
     constructor(props) {
         super(props);
@@ -224,7 +223,7 @@ export default class Autocomplete extends React.Component {
     setSelection(selectionOffset: number) {
         this.setState({selectionOffset, hide: false});
         if (this.props.onSelectionChange) {
-            this.props.onSelectionChange(this.state.completionList[selectionOffset - 1]);
+            this.props.onSelectionChange(this.state.completionList[selectionOffset - 1], selectionOffset - 1);
         }
     }
 
@@ -250,9 +249,8 @@ export default class Autocomplete extends React.Component {
         let position = 1;
         const renderedCompletions = this.state.completions.map((completionResult, i) => {
             const completions = completionResult.completions.map((completion, i) => {
-                const className = classNames('mx_Autocomplete_Completion', {
-                    'selected': position === this.state.selectionOffset,
-                });
+                const selected = position === this.state.selectionOffset;
+                const className = classNames('mx_Autocomplete_Completion', {selected});
                 const componentPosition = position;
                 position++;
 
@@ -261,10 +259,12 @@ export default class Autocomplete extends React.Component {
                 };
 
                 return React.cloneElement(completion.component, {
-                    key: i,
-                    ref: `completion${position - 1}`,
+                    "key": i,
+                    "ref": `completion${componentPosition}`,
+                    "id": generateCompletionDomId(componentPosition - 1), // 0 index the completion IDs
                     className,
                     onClick,
+                    "aria-selected": selected,
                 });
             });
 
diff --git a/src/components/views/rooms/BasicMessageComposer.js b/src/components/views/rooms/BasicMessageComposer.js
index 895696e118..4ec43d8af2 100644
--- a/src/components/views/rooms/BasicMessageComposer.js
+++ b/src/components/views/rooms/BasicMessageComposer.js
@@ -28,7 +28,7 @@ import {
     replaceRangeAndMoveCaret,
 } from '../../../editor/operations';
 import {getCaretOffsetAndText, getRangeForSelection} from '../../../editor/dom';
-import Autocomplete from '../rooms/Autocomplete';
+import Autocomplete, {generateCompletionDomId} from '../rooms/Autocomplete';
 import {autoCompleteCreator} from '../../../editor/parts';
 import {parsePlainTextMessage} from '../../../editor/deserialize';
 import {renderModel} from '../../../editor/render';
@@ -432,8 +432,9 @@ export default class BasicMessageEditor extends React.Component {
         this.props.model.autoComplete.onComponentConfirm(completion);
     }
 
-    _onAutoCompleteSelectionChange = (completion) => {
+    _onAutoCompleteSelectionChange = (completion, completionIndex) => {
         this.props.model.autoComplete.onComponentSelectionChange(completion);
+        this.setState({completionIndex});
     }
 
     componentWillUnmount() {
@@ -535,6 +536,8 @@ export default class BasicMessageEditor extends React.Component {
             quote: ctrlShortcutLabel(">"),
         };
 
+        const {completionIndex} = this.state;
+
         return (<div className={classes}>
             { autoComplete }
             <MessageComposerFormatBar ref={ref => this._formatBarRef = ref} onAction={this._onFormatAction} shortcuts={shortcuts} />
@@ -548,7 +551,13 @@ export default class BasicMessageEditor extends React.Component {
                 onKeyDown={this._onKeyDown}
                 ref={ref => this._editorRef = ref}
                 aria-label={this.props.label}
-            ></div>
+                role="textbox"
+                aria-multiline="true"
+                aria-autocomplete="both"
+                aria-haspopup="listbox"
+                aria-expanded={Boolean(this.state.autoComplete)}
+                aria-activedescendant={completionIndex >= 0 ? generateCompletionDomId(completionIndex) : undefined}
+            />
         </div>);
     }
 
diff --git a/src/i18n/strings/en_EN.json b/src/i18n/strings/en_EN.json
index 5d99d37405..d18a1146b3 100644
--- a/src/i18n/strings/en_EN.json
+++ b/src/i18n/strings/en_EN.json
@@ -1726,11 +1726,16 @@
     "Clear personal data": "Clear personal data",
     "Warning: Your personal data (including encryption keys) is still stored on this device. Clear it if you're finished using this device, or want to sign in to another account.": "Warning: Your personal data (including encryption keys) is still stored on this device. Clear it if you're finished using this device, or want to sign in to another account.",
     "Commands": "Commands",
+    "Community Autocomplete": "Community Autocomplete",
     "Results from DuckDuckGo": "Results from DuckDuckGo",
     "Emoji": "Emoji",
+    "Emoji Autocomplete": "Emoji Autocomplete",
     "Notify the whole room": "Notify the whole room",
     "Room Notification": "Room Notification",
+    "Notification Autocomplete": "Notification Autocomplete",
+    "Room Autocomplete": "Room Autocomplete",
     "Users": "Users",
+    "User Autocomplete": "User Autocomplete",
     "unknown device": "unknown device",
     "NOT verified": "NOT verified",
     "Blacklisted": "Blacklisted",