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About

How we rank & score
Migration guide · Layer 5

SendGrid Postal

What it saves, what actually moves, what you rebuild — and the thing that catches people.

What it costs, and what it saves

SendGrid's Essentials starts near $20/month for 50,000 emails and scales up quickly. Postal self-hosted is a VPS with good IP reputation — around $20/month regardless of volume.

94
Postal
MIT
Effort: Two to four weeks, most of it IP warm-up rather than engineering.

Moves cleanly

SMTP sending. If you send over SMTP, this is a credentials change.

You rebuild

Anything using SendGrid's API, templates or marketing features.

What SendGrid costs you today

Free for 100 emails a day. Essentials from about $20/month for 50,000; Pro from around $90 for 100,000 with a dedicated IP; higher volumes quoted. Marketing Campaigns and dedicated IPs are separate line items. The step that catches people is the jump from free to Essentials — 100 a day is very little, and the next tier is a real monthly commitment for an application sending a few thousand. Figures checked 2026-08-05.

What actually holds you in

Low, and worth knowing before anyone quotes you a migration. Sending is SMTP or a simple API, so switching is credentials and an endpoint. Templates export. What genuinely does not transfer is sender reputation: a new IP or domain starts cold, and mail from a cold IP lands in spam until it is warmed over days or weeks. That is the real cost of switching email providers, it is invisible on a feature comparison, and it is why migrations are staged rather than cut over.

What you are moving to

Postal is a full self-hosted mail platform: sending, receiving, bounce handling, click and open tracking, DKIM signing and a web interface — the parts you would otherwise assemble from Postfix, OpenDKIM and a database. MIT, around 17k stars. It is the only option here where addresses never leave your infrastructure, which for GDPR-sensitive senders is not a preference but a requirement. The honest warning: running a mail server well is a real discipline, and reputation is unforgiving of mistakes.

Free and open source. You supply the server and the IP reputation.

Postal strengths

  • MIT with no enterprise carve-out
  • Recipient addresses never leave your infrastructure
  • Full platform — sending, receiving, bounces, tracking, DKIM
  • No per-email cost at any volume

What you give up

  • You own IP reputation, and warming takes weeks of care
  • Running mail well is a genuine specialism
  • Blocklists are unforgiving of configuration mistakes
  • No shared warmed pool to fall back on

The migration, step by step

  1. 1Get a VPS with a clean IP and confirm the provider allows port 25 outbound — many do not
  2. 2Install Postal, then configure SPF, DKIM and DMARC before sending anything
  3. 3Warm the IP slowly: start at low volume and increase over two to three weeks
  4. 4Migrate transactional sending first and keep marketing on SendGrid until reputation is established
  5. 5Monitor bounce and complaint rates daily during warm-up

The gotcha

Deliverability is the whole game and a new IP has no reputation. Sending your normal volume on day one guarantees the inbox providers treat you as spam. The warm-up is not optional and it cannot be rushed.

When to stay on SendGrid

Deliverability is business-critical and nobody on the team wants to own it — this is the migration most likely to go quietly wrong.

Compare firstAll 5 SendGrid alternatives, rankedWhere this sitsLayer 5Applications

More Layer 5 migrations

Figures verified 2026-08-05 against vendor pricing pages. Prices change and migrations differ by estate — treat the cost delta as a starting model, not a quote. Rankings and recommendations here are merit-only; affiliate income never changes a verdict. See our methodology.

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