For two and a half years, New Outlook for Windows had a signature feature so limited it was barely worth using if you cared about email branding. One signature per account. Applied to everything — new messages, replies, forwards, the lot. Limited formatting. If you’d built a careful corporate signature in Classic Outlook with a logo, social icons, legal disclaimer, and a separate reply variant, you arrived in New Outlook to find that none of it was supported.

That changed in January 2026. Microsoft rolled out an update to email signatures in Outlook on the web and the new Outlook that finally restored something close to the experience known from Outlook Classic — multiple signatures, rich formatting including images and tables, per-context defaults for new messages versus replies and forwards, and a redesigned editor that doesn’t feel like a stripped-down web form.

It’s a meaningful improvement. It’s also still not as good as Classic Outlook’s signature handling in 2026, and there are several pitfalls that will eat hours of your life if you don’t know about them before you start. This guide walks through setting up a signature that actually works — and flags the bits where New Outlook will fight you.

Before you start: do you actually want to do this client-side?

This is the question most people skip, and it’s the most important one if you work in an organisation with more than a handful of users.

Setting up a signature in New Outlook means setting it up on each device, for each user. There’s no built-in deployment mechanism, no group policy template that pushes a signature to everyone in the marketing team, no centralised management. The cloud sync that Microsoft introduced does roam the signature between your own New Outlook installations and the web client, but it doesn’t help your colleague set up the same signature on theirs.

If you’re a single user or a small team, client-side setup is fine. If you’re managing email branding for an organisation of any size, you should be evaluating signature management platforms that deploy server-side via transport rules — Exclaimer, Newoldstamp, WiseStamp, and MySignature all play in this space. These platforms apply signatures at the Exchange transport layer, which sidesteps the entire client-side signature mess and works identically whether your users are on Classic Outlook, New Outlook, OWA, mobile, or third-party clients.

We have a separate piece comparing those platforms specifically against the New Outlook reality if that’s the direction you’re heading. The rest of this article assumes you’re going the client-side route either by preference or because that’s the brief you’ve been given.

Step 1: Open the new signature editor

In New Outlook, click the gear icon in the top-right to open Settings. In the Settings panel, navigate to Accounts → Signatures. If you don’t see “Signatures” as an option there, you’re on a build that hasn’t received the January 2026 update yet — check Help → About New Outlook and confirm you’re on a recent build. If you’re on an older build, the rollout has been progressive and may not have reached your tenant; ask your IT team to confirm whether the update has been deployed.

You’ll see the new signature management view. If you’ve used Classic Outlook’s signature dialog, this will look broadly familiar — a list of signatures on the left, an editor on the right, and controls for default selection at the bottom.

Step 2: Create your signature with the image inserted

Click + New signature. Give it a name that means something to your future self — “Marketing primary 2026”, not “Signature 1”. You’ll thank yourself when you have four signatures for different contexts.

In the editor body, type the text portion of your signature first. Get the formatting right — font, size, colour, line spacing, hyperlinks for your email and website. Resist the temptation to use exotic fonts; signatures render most reliably in standard web-safe fonts because they need to display correctly on recipient systems that don’t have your custom typography installed.

When you’re ready to add the logo or other image, click the Picture icon in the editor toolbar (looks like a small landscape thumbnail), then choose your image file. Alternatively, you can drag the image directly from File Explorer into the editor — that works reliably in the signature editor specifically, unlike the inconsistent drag-and-drop behaviour in the message body, which is covered in our piece on inline images appearing as attachments.

Step 3: Resize the image — and only by the corner handles

Click the inserted image. You’ll see resize handles at the corners and on the sides. Drag a corner handle, not a side handle. Side handles distort the image’s aspect ratio, which looks terrible and is the most common avoidable mistake in signature setup.

Here’s an important non-obvious fact: New Outlook’s signature editor doesn’t compress images on insertion. If your source file is a 2 MB logo at 4000×1500 pixels, that 2 MB will be embedded in every single email you send. Resize the source file in an image editor (Photos, Paint, or any image tool) before you insert it. Aim for a logo width of around 200–400 pixels for the actual display size — small enough that the file weight stays reasonable, large enough to look crisp on high-DPI displays.

Once the image is in and sized correctly, you might want to hyperlink it. Select the image, then use the Insert Link control in the toolbar (or Ctrl+K). Point it at your company website. This is a small touch that increases the click-through rate on signature images by a non-trivial margin.

Step 4: Set defaults — and use the separation New Outlook now gives you

This is the new bit. In the signature settings, you’ll see two dropdown selectors: one for default signature for new messages, one for default signature for replies and forwards. Set them independently. This is the feature that was missing from New Outlook until January 2026 and the single biggest reason the signature experience felt broken for so long.

The standard pattern is to use your full signature with logo, contact details, and disclaimer on new messages, and a shorter signature — name and direct line only — on replies and forwards. Long signatures on reply chains create visual noise that makes email harder to read; short signatures on first contact look unprofessional. The separation lets you have both.

If you’re a heavy user of Microsoft Bookings, the January 2026 update also lets you attach your personal Bookings link per signature. This is buried in the per-signature options rather than being a global setting like it used to be, which is actually an improvement — you might want your Bookings link on outgoing sales emails but not on replies to your finance team.

The image-loading bug you need to know about

Even with the new signature editor working, there’s a known issue you’ll likely encounter: signature images can take noticeably longer to load than you’d expect, and attempting to send a message while signature images are still loading triggers a blocking dialog that prevents the message from being sent.

This was acknowledged by Microsoft in early 2026 and attributed to server-side performance issues affecting rendering of inline images, with regional variations indicating infrastructure capacity problems rather than client-side bugs. In other words: it’s not your machine, it’s Microsoft’s cloud infrastructure, and it’s worse in some regions than others.

The pragmatic workaround is to wait a few seconds after opening a new message before hitting send, particularly for the first message of a session. This sounds like a small thing but in volume sending it adds up.

The more substantive fix — and the one I’d recommend for anyone whose work depends on signatures actually working — is to host the signature image externally and reference it by URL rather than embedding it. This brings us to the other half of the signature question.

Embedded image versus URL-hosted image: which approach to use

When you insert a picture into a New Outlook signature, by default the image is embedded — the actual image bytes are bundled into every email you send. This is straightforward and means recipients see your image even if they’re offline when they read the message.

The alternative is to host the image at a URL — typically on OneDrive, SharePoint, or any public-accessible web server — and use an HTML <img> tag that points to that URL. The image file lives in one place; emails reference it. This is how the larger email signature management platforms work behind the scenes.

The URL-hosted approach has three meaningful advantages over embedding:

  1. It sidesteps the signature-image loading bug. If the image is referenced by URL, the loading happens at the recipient end (when they open your email) rather than at composition time. No blocking dialog when you try to send.
  2. Updates propagate. If you change your logo, you change one file at one URL and every email signature you’ve ever used immediately reflects the new logo when recipients view it. With embedded images, your old logo persists in every previously sent email forever.
  3. Email size stays small. Every embedded image adds weight to every sent message. URL-hosted images don’t add a single byte to your sent mail. For someone sending hundreds of emails a day, this matters.

The disadvantages: recipients who open your email offline won’t see the image. Some email clients block externally-loaded images by default for privacy reasons (Outlook itself does this for emails from senders not in your safe senders list). And you need somewhere stable to host the image.

For setting up URL-hosted signature images via OneDrive: upload your logo to a OneDrive folder, right-click the file and choose Share → Anyone with the link → Copy link. The link OneDrive gives you is a viewer link, not a direct image link — you need to convert it. Replace ?web=1 in the URL with ?download=1, or use the embed-friendly format from SharePoint. Then in your signature editor, you can paste this URL into an inserted image, or — if you’re comfortable with HTML — edit the signature HTML directly to use a custom <img src="https://..."> tag.

This is more setup work upfront. For most users in most situations, it’s worth it.

What still doesn’t work

Even after the January 2026 improvements, a few things in New Outlook signatures fall short of Classic:

  • No HTML source editing in the UI. Classic Outlook signatures could be customised by editing the .htm file directly on disk; New Outlook stores signatures in your mailbox configuration with no exposed file path. If you want custom HTML, you have to paste it through workarounds or use a third-party platform.
  • Limited table layout control. The signature editor supports tables but you can’t fine-tune cell padding, border-collapse behaviour, or other layout details that matter for pixel-perfect signature design.
  • Mobile signatures are separate and plain-text. The mobile Outlook apps support plain text signatures only — you cannot insert an image directly in the mobile signature editor. Outlook for iOS and Android can pull in your desktop signature via Cloud Settings, which syncs settings across Outlook installations, but image rendering on mobile is hit-and-miss compared to desktop.

If you hit any of these limits hard, you’re back to evaluating whether server-side signature management is the right answer for your situation.

A pragmatic recommendation

For most office users sending business email, here’s the version of this that works in 2026:

  1. Set up two signatures in the New Outlook editor: a full one with logo and contact details for new messages, a short one (name and role) for replies and forwards.
  2. Use a properly-sized source image (200–400px wide) rather than letting the editor display-shrink a large file.
  3. If you experience the loading-bug send blocking, switch to URL-hosting the image via OneDrive or SharePoint.
  4. Periodically send yourself a test message from New Outlook and check how it renders on at least one mobile client.

That’s a workable signature setup. It’s not what Classic Outlook gave you four years ago, and the road back to that level of polish involves either patience or a third-party tool. But it’s enough to be presentable, and presentable is the realistic goal for client-side signature management in New Outlook today.