diff --git a/d2m/converters/message-to-event.js b/d2m/converters/message-to-event.js
index 6fdf32e5..978091a5 100644
--- a/d2m/converters/message-to-event.js
+++ b/d2m/converters/message-to-event.js
@@ -175,7 +175,8 @@ async function messageToEvent(message, guild, options = {}, di) {
 				if (!userRegex.some(rx => mxid.match(rx))) {
 					const localpart = mxid.match(/@([^:]*)/)
 					assert(localpart)
-					if (writtenMentionsText.includes(localpart[1].toLowerCase()) || writtenMentionsText.includes(member.display_name.toLowerCase())) addMention(mxid)
+					const displayName = member.displayname || localpart[1]
+					if (writtenMentionsText.includes(localpart[1].toLowerCase()) || writtenMentionsText.includes(displayName.toLowerCase())) addMention(mxid)
 				}
 			}
 		}
diff --git a/d2m/converters/message-to-event.test.js b/d2m/converters/message-to-event.test.js
index 0f9260b7..55245431 100644
--- a/d2m/converters/message-to-event.test.js
+++ b/d2m/converters/message-to-event.test.js
@@ -285,19 +285,19 @@ test("message2event: simple written @mentions for matrix users", async t => {
 						resolve({
 							joined: {
 								"@cadence:cadence.moe": {
-									display_name: "cadence [they]",
+									displayname: "cadence [they]",
 									avatar_url: "whatever"
 								},
 								"@huckleton:cadence.moe": {
-									display_name: "huck",
+									displayname: "huck",
 									avatar_url: "whatever"
 								},
 								"@_ooye_botrac4r:cadence.moe": {
-									display_name: "botrac4r",
+									displayname: "botrac4r",
 									avatar_url: "whatever"
 								},
 								"@_ooye_bot:cadence.moe": {
-									display_name: "Out Of Your Element",
+									displayname: "Out Of Your Element",
 									avatar_url: "whatever"
 								}
 							}
diff --git a/types.d.ts b/types.d.ts
index 6aec80c3..8d40372d 100644
--- a/types.d.ts
+++ b/types.d.ts
@@ -184,7 +184,7 @@ export namespace R {
 
 	export type RoomMember = {
 		avatar_url: string
-		display_name: string
+		displayname: string
 	}
 
 	export type FileUploaded = {