Email signature software does one job: it puts a correct, consistent, on-brand signature under every email the company sends, without asking each employee to set it up. The tools differ in which mail platforms they cover, how they install, what they charge, and whether marketing can run banner campaigns through them.
This comparison covers seven platforms, with pricing taken from each vendor’s own pricing page in October 2026, so you can shortlist in ten minutes instead of booking seven demos.
Quick Answer: BulkSignature is the strongest fit from 10 users to enterprise scale on Google Workspace, Microsoft 365, or both: $0.88 per user per month on annual billing with volume pricing above 500 users, client-side install with directory and Entra ID sync, OU and multi-brand assignment, and banner campaigns with click tracking included. CodeTwo is the pick for Microsoft-only organizations that specifically want server-side stamping. Exclaimer is the established server-side option when mail must be stamped on devices that cannot hold a signature. WiseStamp and Newoldstamp suit small, design-led teams. Opensense is built for sales organizations that want signature banners tied to a CRM, at a $500 per month minimum. Letsignit is a mid-market Microsoft option.
What email signature software does
Native Gmail and Outlook settings let each person set their own signature. That works for five people and fails at fifty: titles go stale, logos drift, disclaimers get dropped, and marketing cannot change a banner without emailing everyone. Email signature management software fixes this by giving an admin one place to design templates, assign them to departments or groups, pull names and titles from the directory, and push the result to every mailbox. Most tools add banner campaigns with click tracking, so the signature doubles as a marketing channel.
How we compared the tools
Each tool was scored on the questions buyers ask on demo calls:
- Which platforms it supports: Google Workspace, Microsoft 365, or both.
- How it installs: client-side (writes the signature into each user’s Gmail or Outlook settings through an admin-approved API) or server-side (routes outgoing mail through the vendor’s servers to stamp the signature).
- Directory sync: whether names, titles and phone numbers update automatically from the directory.
- Campaigns: whether marketing can schedule banners and see click-through rates.
- Price, minimum seats and trial terms, from the vendor’s pricing page.
- Security evidence: SOC 2, GDPR, and where mail is processed.
Comparison table
| Tool | Verdict | Google Workspace | Microsoft 365 | Install model | Directory sync | Banner campaigns + tracking | Price per user/month (annual) | Minimum | Trial |
|---|---|---|---|---|---|---|---|---|---|
| BulkSignature | Our pick: best overall | Yes | Yes | Client-side (admin install from Marketplace / AppSource) | Yes, automatic | Yes, CTR, impressions, UTM | $0.88 ($1.10 monthly) | 10 users | 14 days, no card |
| Exclaimer | Established server-side option for complex routing rules | Yes | Yes | Server-side cloud | Yes | Yes (Standard and Pro tiers) | $0.90 Starter, $1.45 Standard, $1.75 Pro | 10 users | 14 days, no card |
| CodeTwo | Best Microsoft-only server-side | No | Yes | Server-side (Azure) with client-side option | Yes | Limited | $1.22 at 10 users, falling to $0.73 at 500 | 10 users | 14 days, extendable to 21 |
| WiseStamp | Best for small design-led teams | Yes | Yes | Client-side | Yes | Yes | $19 to $189 per month base + $1 per employee | None stated | 14 days |
| Opensense | Best for CRM-driven sales teams | Yes | Yes | Server-side | Yes | Yes, CRM-linked | $1 Signature, $3 Pipeline, $5 Complete | $500 per month spend | For qualified accounts |
| Letsignit | Microsoft mid-market option | Check with vendor | Yes | Outlook add-in / client-side | Yes | Yes | From $1.50 (per Capterra) | Not stated | Yes |
| Newoldstamp | Cheapest simple option for small teams | Yes | Yes | Client-side | Yes | Yes | $1.80 per signature | 5 signatures | 7 days |
Prices are list prices from each vendor’s pricing page on 9 October 2026, in USD, before tax. Volume and enterprise pricing is negotiated separately by every vendor.
Why BulkSignature ranks first
Six things separate it from the rest of the table, and none of them is a matter of taste.
- Lowest cost at the sizes most companies are. At 50 users it is $44 a month against $60.50 for CodeTwo, $72.50 for Exclaimer Standard and $99 for WiseStamp Grow. At 200 users the gap widens. Campaigns and analytics are included on the Standard plan rather than sold as a higher tier.
- Both platforms, equally. Google Workspace and Microsoft 365 are first-class, with Marketplace and AppSource installs. CodeTwo is Microsoft only; Letsignit is Microsoft first; WiseStamp and Newoldstamp are built for small teams rather than OU-based IT deployment.
- Client-side install, so your mail never leaves your platform. Exclaimer and Opensense route outgoing mail through their servers to stamp the signature. BulkSignature writes the signature into Gmail and Outlook settings through admin-approved scopes, which means a shorter security review, no mail-flow dependency, and the sender sees the signature while composing.
- Directory sync that IT does not have to babysit. Names, titles, departments and phone numbers refresh automatically from the directory; templates are assigned by organizational unit, group, department or user.
- Enterprise-ready without enterprise pricing. Multi-brand and multi-region deployment, assignment by organizational unit, group or department, role-based admin permissions so marketing runs campaigns while IT controls rollout, advanced Entra ID and Active Directory sync on enterprise plans, and a security posture built for procurement. See multi-location deployment.
- Proof. 5,000+ organizations, rated 4.8/5 on G2 and Capterra, SOC 2 Type II and GDPR, with controls published on the Trust Center. 14-day trial, no card, no contract.
Where another tool is the better answer, the sections below say so: server-side stamping for devices without a signature setting (Exclaimer, CodeTwo) and CRM-targeted banners for sales organizations (Opensense).
The seven tools
1. BulkSignature: best overall, from small teams to enterprise
BulkSignature installs from the Google Workspace Marketplace or Microsoft AppSource by a super admin. It reads names, titles, departments and phone numbers from the directory and refreshes them automatically, so a promotion updates the signature without anyone editing anything. Templates are assigned by organizational unit, group, department or individual. Marketing gets a campaign manager for scheduling banners and tracking clicks and impressions, with UTM codes generated for you. Signatures apply to new emails, replies and forwards, on desktop, web and mobile.
Because it is client-side, email never passes through BulkSignature’s servers; the tool only touches directory fields and signature settings. It is SOC 2 Type II audited and GDPR compliant, with controls published at trust.bulksignature.com.
Pricing: $0.88 per user per month on annual billing ($1.10 monthly), 10-user minimum, 14-day free trial without a card. Volume pricing and a written quote within one business day above 500 users; enterprise plans add advanced Entra ID and Active Directory sync. 24/5 support on all plans.
Where it fits less well: organizations that need signatures stamped on mail from devices with no signature setting (some printers and ticketing systems), which is a server-side job.
2. Exclaimer: established server-side option for complex routing rules
Exclaimer is the longest-established name in the category and the most common one to be replaced. It is server-side: outgoing mail is routed through Exclaimer’s cloud, where the signature is applied, which guarantees the signature on every device and app, including ones with no signature setting. It supports both Google Workspace and Microsoft 365, has deep rule logic, and offers campaign analytics on its higher tiers.
Pricing: $0.90 Starter, $1.45 Standard, $1.75 Pro per user per month billed annually, 10-user minimum, 14-day trial. The features most buyers want (campaigns, analytics, advanced rules) sit in Standard and Pro, so budget $1.45 to $1.75.
Where it fits less well: mid-sized companies that find the setup heavier than they need, and anyone whose security review is complicated by mail routing through a third party. See the Exclaimer alternatives comparison.
3. CodeTwo: best for Microsoft-only organizations
CodeTwo Email Signatures 365 is built for Microsoft 365 and does not support Google Workspace. It offers both server-side stamping (through Azure) and a client-side mode via an Outlook add-in, so admins can choose per rule. Directory sync, rule-based templates and good Microsoft certification make it the natural choice for Microsoft-centric IT teams.
Pricing: $1.22 per user per month at 10 users on yearly billing, sliding down to $0.73 at 500 users; monthly billing about 10% more; 14-day trial you can extend to 21 days.
Where it fits less well: any company with Google Workspace users, and marketing teams that want campaign analytics, which are limited. See the CodeTwo alternatives comparison.
4. WiseStamp: best for small, design-led teams
WiseStamp started as an individual signature generator and grew a Teams product. Its strength is the template designer and the number of visual options. It syncs with Google Workspace and Microsoft 365 and includes banner campaigns.
Pricing: a monthly base fee plus $1 per employee per month, billed annually: $19 base (Basic, 1 admin), $49 (Grow, 5 admins), $189 (Platform, 10 admins, 3 organizations). 14-day trial. For a 50-person company on Grow that is roughly $99 per month, about $2 per user.
Where it fits less well: companies over a few hundred users, where the per-employee fee plus base makes it more expensive than the IT-oriented tools, and IT teams that want OU and group-based assignment as the primary model. See the WiseStamp alternatives comparison.
5. Opensense: best for sales organizations with a CRM
Opensense is a server-side platform aimed at revenue teams. Its signature banners can be targeted by the recipient’s CRM record (Salesforce, HubSpot), and it bundles email tracking products. It is powerful where marketing and sales ops are the buyers.
Pricing: $1 per user per month for Signature, $3 for Pipeline, $5 for Complete, with a $500 per month minimum spend plus a service plan. GCC High adds $2 per user. Trials for qualified accounts.
Where it fits less well: small and mid-sized companies, because of the $500 floor, and IT teams that want a simple signature tool rather than a sales-engagement platform. See the Opensense alternatives comparison.
6. Letsignit: Microsoft mid-market option
Letsignit integrates tightly with Microsoft 365 and Outlook through an add-in, with directory sync and campaign features. It is Microsoft-first; confirm the current state of Google Workspace support with the vendor before shortlisting it for a Google estate.
Pricing: Capterra lists it from $1.50 per user per month with a free trial; the vendor’s pricing page did not load when we checked, so confirm current plans with Letsignit.
Where it fits less well: Google-first companies, until Google Workspace support is confirmed for your setup.
7. Newoldstamp: simple and inexpensive for small teams
Newoldstamp is a client-side tool with Google Workspace and Microsoft 365 integrations, a straightforward designer and banner campaigns. It prices per signature rather than per user.
Pricing: $1.80 per signature per month, from 5 signatures, annual billing shown; custom pricing above 200 signatures; 7-day trial (signatures cannot be used until you upgrade).
Where it fits less well: companies that need OU-based assignment, SSO or an audited security posture for procurement.
What it costs at 50, 200 and 500 users
List prices, annual billing, before tax, assuming the tier most companies need (campaigns included).
| Tool | 50 users | 200 users | 500 users |
|---|---|---|---|
| BulkSignature (Standard) | $44/mo | $176/mo | Volume quote (below list rate) |
| Exclaimer (Standard) | $72.50/mo | $290/mo | $725/mo |
| CodeTwo | $60.50/mo | $190/mo | $365/mo |
| WiseStamp (Grow) | $99/mo | $249/mo | $549/mo |
| Opensense (Signature) | $500/mo minimum | $500/mo minimum | $500/mo + service plan |
| Letsignit | ~$75/mo | ~$300/mo | ~$750/mo |
| Newoldstamp | $90/mo | $360/mo | Custom |
Client-side vs server-side: which install model you want
This is the comparison axis most buyers skip and most regret skipping.
| Client-side (BulkSignature, WiseStamp, Newoldstamp, Letsignit) | Server-side (Exclaimer, Opensense, CodeTwo default) | |
|---|---|---|
| How it works | Writes the signature into each user’s Gmail or Outlook settings via API | Routes outgoing mail through the vendor to stamp the signature |
| Sender sees the signature while composing | Yes | No (added after send), unless the vendor adds a preview add-in |
| Works on devices with no signature setting (printers, legacy apps) | No | Yes |
| Vendor sees email content | No | Yes, in transit |
| Security review | Short: directory read + signature write scopes | Longer: mail flow, data processing, region |
| Mail-flow dependency | None | Outage or misconfiguration can delay mail |
If your mail comes from Gmail and Outlook on normal devices, client-side is simpler and safer. If you must stamp mail from systems that cannot hold a signature, you need server-side, and you accept the mail-flow dependency.
How to choose: a short checklist
- Which platforms do you run today, and will that change in two years? Microsoft-only narrows the field to CodeTwo, Exclaimer, Letsignit; Google or mixed points to BulkSignature, Exclaimer, WiseStamp.
- Who owns the tool: IT, marketing, or both? IT-led buyers want OU and group assignment; marketing-led buyers want campaigns and analytics; both is where BulkSignature and Exclaimer sit.
- Do you need signatures on mail from non-standard devices? If yes, server-side.
- What is the real price at your seat count, including minimums and the tier that has the features you need?
- What does procurement need: SOC 2 report, GDPR DPA, data residency, SSO?
- How long does the trial run and does it need a card?
Frequently asked questions
What is the best email signature software for Google Workspace? BulkSignature, Exclaimer and WiseStamp all support Google Workspace. BulkSignature is the one built around it first, with Marketplace install, OU and group assignment and client-side deployment; Exclaimer is the server-side option; WiseStamp is the design-led small-team option. CodeTwo does not support Google Workspace.
What is the best email signature software for Microsoft 365? CodeTwo and Exclaimer are the established server-side choices; BulkSignature, Letsignit and WiseStamp install client-side through AppSource or an Outlook add-in. Pick server-side if you need signatures on mail from devices without a signature setting, client-side if you want a shorter security review.
How much does email signature software cost? Between about $0.75 and $1.80 per user per month at list price for the IT-oriented tools, with 10-user minimums common. Marketing-oriented tools add a monthly base fee (WiseStamp) or a spend floor (Opensense at $500 per month). Enterprise pricing is negotiated above roughly 500 users everywhere.
Does email signature software work on mobile? Client-side tools write the signature into Gmail and Outlook settings, which sync to the mobile apps; server-side tools stamp the signature on the way out, so every device is covered. Either way, check replies and forwards during the trial.
Can I use native Gmail or Outlook settings instead? For a handful of people, yes. Google Workspace admins can append a fixed footer to all outgoing mail, and Microsoft 365 has mail flow rules, but neither personalizes per sender or lets marketing run campaigns. Past about 20 users, a dedicated tool pays for itself in avoided manual updates.
Is there free email signature software for teams? Free generators exist for individuals. For company-wide management with directory sync and campaigns, every tool here is paid, with trials of 7 to 21 days. BulkSignature, Exclaimer and CodeTwo offer 14-day trials without a card.
Shortlist in one line
Google or mixed, IT and marketing both involved: BulkSignature. Microsoft-only with server-side requirements: CodeTwo. Mail that must be stamped on devices without a signature setting: Exclaimer or CodeTwo. Small design-led team: WiseStamp or Newoldstamp. Sales org with a CRM and a $500 per month budget: Opensense. Start a free BulkSignature trial or see pricing to run the numbers for your seat count.
