Every email signature platform makes essentially the same promise: a beautiful, on-brand signature with your logo, social icons and banner, applied consistently across your whole organisation. The promise is identical because the marketing is identical. What the marketing universally avoids saying out loud is the one thing that decides whether any of these tools will actually work for you in 2026: how the signature gets onto the email. Get that architectural question wrong and you’ll pay for a product that produces a gorgeous signature your recipients see as a broken-image icon, an attachment, or nothing at all.
That question matters more than ever because Outlook itself has fractured. The New Outlook for Windows — the web-technology-based client Microsoft is steering everyone toward — handles images and add-ins differently from Classic Outlook, and it has been a moving target for two years. A signature platform that worked perfectly in Classic Outlook can quietly stop applying signatures the way you expect once a user migrates. So this comparison judges WiseStamp, MySignature, Newoldstamp and Exclaimer not on how pretty their template galleries are — they’re all fine — but on the thing that determines real-world reliability: their deployment model and how it survives contact with the New Outlook reality.
Pricing throughout is approximate and current as of May 2026. This category changes its pricing and packaging frequently, vendors quote per-mailbox costs that shift with volume and contract length, and published figures often lag the real quote. Treat every number here as a starting point to verify, not a contract.
The one distinction that actually matters: client-side vs server-side
Before any feature table, understand the two fundamentally different ways these products work, because it predicts almost everything else.
Client-side (the signature is injected at the user’s end.) Tools in this camp install a browser extension, a local add-in, or rely on the user pasting generated HTML into their mail client’s signature settings. The signature lives on the device. WiseStamp and MySignature are, at their core and especially on their individual and small-team tiers, built around this model.
The appeal is obvious: no IT involvement, set up in minutes, cheap. The structural weakness is just as obvious once you say it plainly: the signature depends entirely on the client cooperating. And the New Outlook for Windows is notably less cooperative than Classic Outlook was — it doesn’t support the same add-in mechanisms, browser extensions don’t reach it, and roaming-signature behaviour has been inconsistent through its rollout. Client-side tools have been scrambling to adapt, but you are betting your branding on Microsoft’s client behaving, and Microsoft’s client has been changing under everyone’s feet.
Server-side (the signature is stamped centrally, in the mail flow.) Tools in this camp connect to Microsoft 365 (or Exchange, or Google Workspace), sync your users from the directory, and apply the signature server-side as mail passes through — before it reaches the recipient, regardless of what client the sender used. Exclaimer is the clearest example here. CodeTwo is the other big name in this space, though it’s outside this particular comparison.
The appeal is reliability: because the stamping happens in the mail flow and not on the device, it doesn’t care whether the sender is on New Outlook, Classic Outlook, the web app, or a phone. The signature is applied the same way every time. The cost of that reliability is real: it’s an IT-deployed, per-mailbox, minimum-seat-count product, and it’s genuinely more expensive and more involved to set up.
If you remember one sentence from this article: client-side tools optimise for setup speed and price; server-side tools optimise for consistency and surviving Microsoft’s client churn. Almost every difference below flows from that.
The comparison at a glance
| Platform | Model | Typical price (2026) | Min users | New Outlook reliability | Best for |
|---|---|---|---|---|---|
| WiseStamp | Client-side (extension/paste) | ~$1–$2 /user/mo | 1 | Patchy — depends on client cooperation | Individuals, small teams, freelancers |
| MySignature | Client-side, generator-first | ~$1.50–$4 /user/mo range | 1 | Patchy — same client dependency | Individuals and small teams wanting polish cheaply |
| Newoldstamp | Generator + some central management | from ~$7 /mo entry, scales per user | low | Mixed — better on managed flows | Small-to-mid teams running signature marketing |
| Exclaimer | Server-side stamping | ~$0.90–$1.75 /user/mo | 10 | Strong — client-agnostic by design | Organisations that need guaranteed consistency |
The price column tells a story that runs against the usual “expensive = better” instinct. Exclaimer’s per-user price is often the lowest of the four at scale, not the highest — because it’s sold to organisations by the mailbox, while the client-side tools price per individual and add up fast for a team. The “cheap” tools are frequently the expensive ones once you have fifty employees.
WiseStamp: excellent for one person, riskier for an organisation
WiseStamp is the most recognisable consumer name in this space, with a very large user base and a deservedly good reputation for one specific job: helping an individual or a small team produce a sharp, professional signature without design or IT help. The editor is friendly, the templates are good, and the dynamic elements — banners, social icons, scheduling links, even video — work as advertised for the sender who sets it up.
The scepticism kicks in the moment you scale past a handful of people, and it has two prongs.
First, the deployment model. WiseStamp is fundamentally client-side. For Gmail it leans on a browser extension; for Outlook it has historically depended on add-ins and signature application that the New Outlook for Windows does not reliably support. User reviews are blunt about this — among the recurring complaints is that it doesn’t work with New Outlook and only with certain versions of Classic Outlook. WiseStamp has been working to support managed deployment and broader client coverage, but if your organisation is mid-migration to New Outlook, “depends which client and which version” is not a reassuring foundation for company-wide branding.
Second, the commercial conduct. This is the part the review-site star ratings smooth over. There’s a notable thread of customer complaints about billing and cancellation — charges continuing without clear notice, cancellation options that are hard to find in the dashboard, invoices not arriving. None of that affects signature quality, but a consumer-advocacy read has to flag it: a tool that’s easy to start and awkward to stop is a tool to enter with your eyes open and your renewal date in your calendar.
Verdict: genuinely good for an individual or a tiny team that lives in Gmail or Classic Outlook. For an organisation standardising across mixed and migrating Outlook clients, the client-side dependency makes it a gamble, and the billing friction is a reason to read the cancellation terms before you read the template gallery.
MySignature: the budget polish play, same structural ceiling
MySignature occupies similar territory to WiseStamp — a generator-first product aimed at individuals and small teams who want an attractive signature cheaply — and it competes largely on price and template design. For the solo professional or the five-person agency, it does the job, and it does it for not much money.
The honest assessment is that MySignature shares WiseStamp’s structural ceiling. It’s a client-side, generated-HTML / extension-based approach, which means it inherits the same vulnerability: the signature’s fate is in the hands of whatever mail client the user opens, and the New Outlook for Windows is the least predictable of those clients. The template editor and the banner features are perfectly competent. What you’re not buying, at the entry tiers, is the guarantee that the signature lands identically for every employee on every device — because that guarantee can’t really be made by a tool that depends on the client.
There’s a broader pattern worth naming here, because it applies to both WiseStamp and MySignature: the marketing for client-side tools talks about “company-wide consistency” and “centralised management,” and at the higher business tiers they do add genuine admin controls. But “centralised management of a client-side mechanism” is still constrained by the client-side mechanism. You can manage the templates centrally; you cannot make a non-cooperating client cooperate. Read the tier you’re actually buying, not the feature list of the tier above it.
Verdict: a reasonable, affordable choice for individuals and small teams who want better design than they’d build themselves and who live in cooperative clients. Not the tool to bet an organisation’s brand consistency on during an Outlook migration.
Newoldstamp: the marketing-oriented middle ground
Newoldstamp positions itself a notch more toward teams and, specifically, toward using the signature as a marketing channel — banner campaigns, analytics on signature link clicks, department-level template control. Its entry pricing starts higher than the consumer tools (in the region of $7 and up per month, scaling with users), which signals its intended buyer: the small-to-mid marketing or sales team that wants the signature to do work, not just look tidy.
Where Newoldstamp earns a more favourable note than the pure consumer tools is that it offers more genuine central management and supports more managed deployment paths, which makes its behaviour somewhat less hostage to the individual client than a pure paste-the-HTML approach. “Somewhat less,” not “immune” — the New Outlook caveat still applies to any approach that ultimately relies on the client applying the signature, and you should test it against your actual environment rather than trust the compatibility checklist.
The scepticism here is about scope creep and value. The signature-marketing features are real, but they’re only valuable if you’ll actually run signature campaigns and look at the analytics. A lot of teams pay for the marketing tier and use it as an expensive template manager. If you’re not going to run banner campaigns, you’re paying for a capability you won’t touch — and a cheaper tool, or a server-side tool, would serve you better.
Verdict: the right pick if signature-as-marketing-channel is a real part of your plan and you have a team to justify the management features. Overspecified, and therefore poor value, if you just want consistent signatures.
Exclaimer: the boring, reliable, organisation-grade choice
Exclaimer is the least exciting product in this comparison and, for most organisations, the correct one — which is exactly the kind of conclusion the affiliate-driven roundups resist, because the consumer tools convert better.
Exclaimer is server-side. You connect Exclaimer Cloud to Microsoft 365, sync users from your directory, and signatures are stamped onto outgoing mail centrally. The consequences are the whole pitch:
- It is client-agnostic. New Outlook, Classic Outlook, Outlook on the web, the mobile apps — the signature is applied in the mail flow, so it doesn’t matter which one the sender used. In a world where your users are mid-migration to New Outlook, this is the feature that actually solves the problem the other tools struggle with.
- It enforces consistency. Because users can’t fail to apply, paste wrong, or have an extension break, every email genuinely carries the right signature.
- Per-mailbox pricing is competitive at scale, often landing around $0.90–$1.75 per user per month depending on tier, volume and contract — frequently cheaper per head than the consumer tools once you’re past a few dozen people, with a minimum of around 10 users.
Now the honest costs, because a consumer-advocacy review owes you these:
- It’s an IT project, not a five-minute setup. You’re connecting it to your tenant, syncing directory data, and routing mail through it. For larger deployments, professional services for setup and template design can run into the thousands. This is not a freelancer’s tool.
- It routes your mail through an external service to stamp it, and some administrators report associated friction — occasional routing delays, mail-flow complexity, and the general caution that comes with putting a third party in your send path. These are manageable and expected for this category of tool, but they’re real and worth planning for.
- The marketing leans on enterprise logos and “billions of signatures delivered.” Impressive, and also exactly the kind of social proof that’s designed to make a small business feel it must buy the enterprise tool. If you have 12 people and no compliance requirement, the heavyweight server-side machinery may be more than you need.
Verdict: if signature consistency across a real organisation is a requirement — for branding, for legal disclaimers, or simply for surviving the New Outlook transition without a flood of “my logo’s broken” tickets — Exclaimer (or a server-side competitor like CodeTwo) is the architecturally correct answer, and frequently the better-value one per user than its “cheaper” rivals.
So which should you actually choose?
Strip away the template galleries and it comes down to who you are.
- A freelancer or solo professional: WiseStamp or MySignature. You control your own client, the client-side limitation barely affects one person, and you don’t need to pay for server-side machinery. Just diarise your renewal date.
- A small team that lives in Gmail or Classic Outlook and isn’t migrating soon: the consumer tools still work. Test on the exact clients your people use.
- A small-to-mid team that wants the signature to be a marketing channel: Newoldstamp, if and only if you’ll genuinely use the campaign features.
- Any organisation standardising across mixed Outlook clients, mid-migration to New Outlook, or with legal-disclaimer requirements: server-side, meaning Exclaimer or a peer. The reliability is the product, and the per-user economics usually favour it at scale anyway.
What to test before you pay anyone
The free trials these platforms offer are worth using properly, and most people don’t — they admire the template editor and skip the only tests that actually predict whether the tool will work for them. Run these four before you commit:
Send to yourself across every client your people use. Set up a signature, then send a test email and open it in Classic Outlook, New Outlook, Outlook on the web, and a phone. The signature that looks perfect in the editor is irrelevant; the signature that arrives intact in all of those is the only one that counts. This single test exposes the client-side tools’ weakness faster than any review can describe it.
Send to an external recipient on a different platform. Send to a Gmail address, a different organisation’s Microsoft 365, anywhere outside your own walls. Images that embed fine internally sometimes arrive as attachments or broken links externally — which is, not coincidentally, one of the most common Outlook signature complaints there is.
Check what happens to the logo specifically. Does the image embed, or does it link to a hosted URL? Linked images can break if the host changes; embedded images can arrive as attachments. Knowing which approach the tool uses tells you which failure mode you’re signing up for.
Find the cancellation path before you subscribe. Open the billing section and locate the cancel option now, during the trial. If you can’t find it easily, that tells you something — and the WiseStamp billing complaints exist precisely because people skipped this step.
The reason organisations end up server-side anyway
There’s a driver behind the server-side tools that the consumer comparison underplays: legal disclaimers and compliance. Many organisations are required — by regulation, by industry rules, or by their own legal counsel — to append a specific disclaimer to every outgoing email. Not most emails. Every email.
A client-side tool cannot guarantee that. If the signature depends on the user’s client cooperating, then any email sent from a misconfigured client, a new starter who hasn’t set up the extension, or a phone that doesn’t support the add-in goes out without the disclaimer. For a marketing signature, that’s untidy. For a mandated legal disclaimer, it’s a compliance gap.
Server-side stamping closes that gap by design, because the application happens in the mail flow and the user can’t fail to apply it. This is the unglamorous reason a great many organisations that started with a cheap client-side tool eventually migrate to Exclaimer or CodeTwo — not because the templates are better, but because “every email, no exceptions” is a requirement only the server-side model can actually meet. If you have a compliance obligation, this isn’t a preference; it’s the deciding factor, and it should move you to the server-side column before you compare anything else.
The problem underneath all of this
A platform helps, but it doesn’t dissolve the underlying behaviour that makes Outlook signatures fragile in the first place. Even with a tool in place, you’ll still run into the classics — the signature image arriving as an attachment instead of inline, which is fundamentally about how Outlook embeds versus links images, and the specific setup steps a working image signature needs in New Outlook. Server-side tools paper over a lot of this by controlling the stamping; client-side tools leave you exposed to it. If you’re on Exchange specifically, the inline-image behaviour for Exchange accounts interacts with server-side stamping in ways worth understanding before you deploy.
The single most useful thing this comparison can leave you with is the question to ask any signature vendor before you pay them: not “how good are your templates,” but “how, exactly, does the signature get applied — and what happens to it when my users move to New Outlook?” The ones with a confident, specific answer to the second half of that question are the ones worth your money.