Switching from SendGrid, with your code intact

The fastest exit is the one that doesn't touch your code. The endpoint mapping below is verified against what our API actually accepts, the timelines are honest about what moves by hand, and the pricing is dated and sourced.

Facts verified 2026-08-29 — corrections: hello@emailfast.dev

The whole code change

  import sgMail from "@sendgrid/mail";
+ import sgClient from "@sendgrid/client";

+ sgClient.setDefaultRequest("baseUrl", "https://api.emailfast.dev");
+ sgMail.setClient(sgClient);
- sgMail.setApiKey(process.env.SENDGRID_API_KEY);
+ sgMail.setApiKey(process.env.EMAILFAST_API_KEY); // ef_sandbox_… works everywhere

That is the migration for a send-call integration — a base URL and a key, because SendGrid-, Mailgun-, and Postmark-compatible endpoints: point your existing SDK at a new base URL with a new key and keep your code — attachment sends are the one exception, refused with a clear error in your provider's own format rather than silently dropped. What the compatible endpoint actually honors, verified against the code that serves it:

• POST /v3/mail/send, same shape. Same Bearer auth, same body, and the success your code expects: an empty-body 202 with an X-Message-Id header.
• cc, bcc, and send_at carry over. Each personalization's cc/bcc ride on every message fanned from it, and send_at — top-level or per-personalization — schedules the send.
• Personalizations fan out to one message per recipient. One honest difference: where SendGrid sends one message per personalization, we deliver each recipient their own copy — a personalization with several to addresses becomes that many copies, each carrying its cc. If any recipient is blocked by policy, the whole call rolls back and returns a truthful 4xx — nothing half-queued for a retry to double-send.
• template_id sends resolve today. Re-create the template in the dashboard or over POST /v1/templates with the slug set to your old SendGrid id — d-… ids are valid slugs — and the compat send works unchanged. An unknown id returns a SendGrid-shaped 400 naming it.
• Attachments are refused loudly. Outbound attachments aren't supported yet, platform-wide; a send carrying one gets a SendGrid-shaped 400 errors[] entry saying so — never a message quietly delivered without its file. SendGrid-only knobs with no equivalent here (categories, custom_args, mail_settings, and the like) are accepted without effect; native platform policy applies.
• An Idempotency-Key header makes retries safe — something the SendGrid send endpoint never offered: a 202 from the API means the send is committed to a durable, partitioned outbox before we answer — a crash can't lose it, and a retry with the same idempotency key can't double-send.

Behind the compatible surface, every send passes the same checkpoint as every other ingress: every send — REST, SMTP, browser SDK, compatibility endpoints, broadcasts, automations — passes through one admission gate: idempotency, suppression, quota, and content policy in a single checkpoint no ingress can skip.

How long it actually takes

Honest ranges, tied to the path above — not a slogan:

Test the whole thing before production traffic moves: sandbox keys (ef_sandbox_…) that run the real pipeline dry: real validation, real rendering, real events, a hosted capture inbox — and no email leaves.

What SendGrid publishes at your volume

Detail: Forever-free plan no longer advertised: 'Free trial lets you send 100 emails/day for 60 days'. Public page publishes only 'starting at' prices per band: Essentials starting $19.95/mo for 50,000-100,000 emails/mo; Pro starting at $89.95/mo for 100,000-2,500,000 emails/mo (includes 1 dedicated IP, SSO, subusers); Premier custom. Exact per-volume prices within bands (e.g. Essentials at 100k, Pro at 300k/500k/700k) are no longer published on the public page - they surface only in the signup flow. 'Taxes and overages may apply' with no public overage rate.

Not published / not verified: Exact Essentials price at 100k sends; Pro per-volume prices (300k/500k/700k/1.5M/2.5M); Overage rates (page says 'overages may apply' without rates).

Figures verified 2026-08-29 on the SendGrid (Twilio) pricing page, promo and intro discounts excluded — method and corrections via the claims methodology.

Price your own numbers against every surveyed platform — a scenario is shareable as a link: 50,000 sends/month, 100,000, or 500,000.

Where Email Fast stands

Our stake, declared: we make Email Fast, and these are the launch prices already published on our pricing page — during early access they may be refined before general availability, and self-serve checkout opens at GA. Contacts and subscribers are never billed, at any list size.

Where SendGrid wins

From our own pricing survey, their side stated plainly — Massive proven scale and deliverability infrastructure, the broadest SDK/integration ecosystem in email, marketing + transactional under one roof, and Twilio SMS/voice adjacency.

Two honest additions. Twilio's trust center holds third-party attestations we don't have yet — our security page says exactly what is and isn't certified. And if you want email, SMS, and voice under one vendor and one bill, Twilio is that vendor and we are not. The full comparison, including when to stay: SendGrid vs Email Fast.

Next

• The step-by-step migration guide — including domain verification
• Also pricing Mailgun or Postmark?
• Suspended by your current platform? Read that first.
• Apply for early access — live sending starts by application

SendGrid is a trademark of its owner; Email Fast is not affiliated with or endorsed by them. SendGrid facts were verified on their public pages on the dates shown — corrections: hello@emailfast.dev.