diff --git a/ElementX/Sources/Other/Avatars.swift b/ElementX/Sources/Other/Avatars.swift
index 29711a08c..39f4857d8 100644
--- a/ElementX/Sources/Other/Avatars.swift
+++ b/ElementX/Sources/Other/Avatars.swift
@@ -8,6 +8,7 @@
 
 import Foundation
 import SwiftUI
+import UIKit
 
 enum Avatars {
     enum Size {
@@ -38,6 +39,28 @@ enum Avatars {
         }
     }
     
+    /// Media repo thumbnails are scaled, not cropped, so they keep the source's aspect
+    /// ratio. System UI (share sheet suggestions, notifications) stretches non-square
+    /// images to fill its circle, so centre-crop to a square before donating them.
+    nonisolated static func squareAvatarImageData(from data: Data) -> Data? {
+        guard let image = UIImage(data: data) else { return nil }
+
+        let side = min(image.size.width, image.size.height)
+        guard side > 0 else { return nil }
+
+        if image.size.width == image.size.height {
+            return data
+        }
+
+        let format = UIGraphicsImageRendererFormat()
+        format.scale = image.scale
+
+        return UIGraphicsImageRenderer(size: CGSize(width: side, height: side), format: format)
+            .pngData { _ in
+                image.draw(at: CGPoint(x: (side - image.size.width) / 2, y: (side - image.size.height) / 2))
+            }
+    }
+
     @MainActor
     static func generatePlaceholderAvatarImageData(name: String, id: String, size: CGSize) -> Data? {
         let image = PlaceholderAvatarImage(name: name, contentID: id)
diff --git a/ElementX/Sources/Services/Timeline/TimelineController/TimelineController.swift b/ElementX/Sources/Services/Timeline/TimelineController/TimelineController.swift
index a568d958f..c22dc19ae 100644
--- a/ElementX/Sources/Services/Timeline/TimelineController/TimelineController.swift
+++ b/ElementX/Sources/Services/Timeline/TimelineController/TimelineController.swift
@@ -650,8 +650,9 @@ class TimelineController: TimelineControllerProtocol {
         }
         
         if let avatarURL, let mediaSource = try? MediaSourceProxy(url: avatarURL, mimeType: nil) {
-            if case let .success(avatarData) = await mediaProvider.loadThumbnailForSource(source: mediaSource, size: .init(width: 100, height: 100)) {
-                sendMessageIntent.setImage(INImage(imageData: avatarData), forParameterNamed: \.speakableGroupName)
+            if case let .success(avatarData) = await mediaProvider.loadThumbnailForSource(source: mediaSource, size: .init(width: 100, height: 100)),
+               let squareAvatarData = Avatars.squareAvatarImageData(from: avatarData) {
+                sendMessageIntent.setImage(INImage(imageData: squareAvatarData), forParameterNamed: \.speakableGroupName)
             } else {
                 addPlacehoder()
             }
diff --git a/NSE/Sources/NotificationContentBuilder.swift b/NSE/Sources/NotificationContentBuilder.swift
index c4ed82f6b..7bb218394 100644
--- a/NSE/Sources/NotificationContentBuilder.swift
+++ b/NSE/Sources/NotificationContentBuilder.swift
@@ -259,7 +259,9 @@ nonisolated struct NotificationContentBuilder {
            let mediaSource = icon.mediaSource {
             switch await mediaProvider.loadThumbnailForSource(source: mediaSource, size: .init(width: 100, height: 100)) {
             case .success(let data):
-                fetchedImage = INImage(imageData: data)
+                if let squareData = Avatars.squareAvatarImageData(from: data) {
+                    fetchedImage = INImage(imageData: squareData)
+                }
             case .failure(let error):
                 MXLog.error("Couldn't add sender icon: \(error)")
             }