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Vendor comparison

Exclaimer vs. CodeTwo — the two big server-side platforms.

If you've narrowed it to Exclaimer vs CodeTwo you're already committed to server-side signature injection, and you're almost certainly on Microsoft 365. Good news: both products are mature and neither is a bad pick. The differences are real but subtle — this is the honest breakdown.

Pricing reflects published tiers as of early 2026.

Exclaimer
CodeTwo
Architecture
Server-side injection via Microsoft 365 mail-flow connector (also Google Workspace).
Server-side injection via Microsoft 365 mail-flow connector (Azure infrastructure).
Platforms
Microsoft 365 + Google Workspace.
Microsoft 365 only.
Pricing (per mailbox/mo, annual)
~$1.50–$3.30 depending on tier.
~$1.30–$2.30 depending on tier.
Template designer
More polished, drag-and-drop, richer preview.
Functional, form-based, faster for a technical admin.
Campaign module
Full A/B testing, scheduling, targeting rules on higher tiers.
Scheduling and targeting; A/B testing more limited.
Directory integration
Entra ID, Google Directory attribute mapping.
Deep AD / Entra ID mapping — often the pick for complex per-department rules.
Mobile-sent mail
Covered automatically.
Covered automatically.
Setup
3–5 days including DNS + pilot.
3–5 days including DNS + pilot.
Best for
Marketing-led enterprise deployments, especially where banner campaigns are the reason to buy.
IT-led enterprise deployments on Microsoft 365 where budget and directory-driven rules matter most.
Pick Exclaimer if
  • • Marketing is driving the buy — banner campaigns matter.
  • • You need Google Workspace support too.
  • • You want the polished designer and richer preview.
  • • A/B testing signatures is a real requirement.
Pick CodeTwo if
  • • Microsoft 365 only and IT is driving.
  • • Per-mailbox cost matters at your headcount.
  • • Deep directory-attribute rules are non-negotiable.
  • • You want a technical admin console over a marketing one.
Under 200 mailboxes? Reconsider server-side entirely.

Server-side injection is the right architecture at 500+. Under 200 the mail-flow connector project is usually more overhead than the problem it solves. Wren is client-installed, centrally designed, has the swappable banner as its core feature, and is flat $99/mo up to 50 people or $199/mo up to 100 — no per-mailbox billing, no connector, no DNS changes. Design one free →

Related: Exclaimer vs WiseStamp · CodeTwo vs WiseStamp · Wren vs Exclaimer · Wren vs CodeTwo