Problem
You wish to understand which functions of Signature 365 client-side signatures are supported in your version of Microsoft Outlook.
Solution
The tables below list the supported versions of Outlook for Windows and supported features of the Outlook modern add-in and Classic Agent.
Version requirements for Outlook can be found in Signature 365 system requirements.
Outlook Modern Add-in
| Outlook / Office version | Support for Modern Add-in | Limitations | Comments |
|---|---|---|---|
| Office 365 (All SKU's) | Yes | - | (1) |
| Outlook on the Web | Yes | - | (2) |
| Outlook App for Android | Yes | (3) | |
| Outlook App for iOS | Yes | (3) | |
| Microsoft Office for Mac | Yes | (4) | |
| Office Pro / Pro Plus Retail (2021 2024) | Partial | (5) | |
| Office Standard (2021 / 2024) | Partial | (5) | |
| Office VLSC versions (2021 / 2024) | Partial | (5) | (6) |
| Office Home & Business (2021 / 2024) | Partial | (5) | (6) |
| Office Home & Student (2021 / 2024) | Partial | (6) | (6) |
| "Microsoft Store" Office versions | No | Not supported | Non 365 versions purchased from the windows store app are not supported |
| Microsoft Office 2016 / 2019 | No | Not supported | Cannot be supported due to the requirement for NAA authenication (7) |
(1) Requires a Microsoft supported version of Outlook, please see the following article for Microsoft supported Office versions.
Update history Microsoft 365 apps by date
(2) Supported browsers: Google Chrome, Microsoft Chromium Edge, Mozilla Firefox, Apple Safari on Mac.
(3) Outlook Mobile only supports automatically inserting signatures. The task pane for choosing signatures, changing settings and user data is not supported.
(4) Requires Outlook New UI Outlook for Mac - Microsoft Support
(5) Server-side signatures with signature preview and sent-items update fully supported.
(6) Auto insertion of signatures is not supported on non-Office 365 licenced versions of Outlook. Signature must be selected by user to insert. Add-in must be installed via custom XML.
(7) Please see New Nested App Authentication for Office Add-ins for more details.
Outlook Classic Agent
The Outlook classic agent is supported on all supported Outlook versions from 2016 onwards. Installation instructions, requirements and limitations for the Classic Add-in can be found in this article: How to install the Outlook Classic Agent