SMTP2GO is a reliability-focused SMTP relay and email API with a long-standing free tier, popular for getting application and device email delivered with minimal fuss.
SMTP2GO Starter is $15/month for 10,000 emails. SendDart’s entry plan costs slightly less and includes 50,000 emails, 2,500 contacts, and 10 domains.
On SMTP2GO, 100k volume plus dedicated IP territory starts at $75/month. SendDart’s Pro 100k is a third of that, and Scale — with the dedicated-IP add-on — still lands well under it.
SMTP2GO moves mail; audiences, segments, campaigns, automations, A/B tests, polls, and AI template tooling are not what it does. SendDart includes all of it in every plan.
3,000 emails/month free versus 1,000 — both permanent, both card-free, but SendDart’s also includes contacts and campaign tools.
If you need a pure SMTP relay for legacy software, printers/scanners/devices, or an app you cannot modify beyond SMTP credentials, SMTP2GO is built precisely for that. SendDart is HTTPS-API-first and does not currently expose raw SMTP.
The free tier (3,000 emails/month, 100/day) needs no card — enough to verify the whole migration end to end before paying anything.
Add your sending domain, copy the DKIM, SPF, and DMARC records into your DNS provider, then click Verify in SendDart. Allow for DNS propagation before testing delivery.
Replace your current send with one HTTPS request or a typed SDK in 8 languages. Batch endpoints, idempotency keys, and scheduling are built in.
Subscribe a webhook to delivered, opened, clicked, bounced, complained, and unsubscribed events — every request is signed so you can verify the source.
Bring audiences over via CSV or the contacts API; templates port as plain HTML or rebuild in the block editor.
The send call, after the switch
curl -X POST https://www.senddart.com/api/emails \
-H "Authorization: Bearer mb_xxxxxxxx" \
-H "Content-Type: application/json" \
-d '{
"from": "Acme <hello@acme.com>",
"to": ["delivered@test.senddart.com"],
"subject": "Welcome to Acme",
"html": "<p>You are in.</p>"
}'The sending domain is taken from the address in from — there is no domain field on this endpoint. delivered@test.senddart.com is the test recipient that reports a delivered outcome without sending real mail.
| Feature | SendDart | SMTP2GO |
|---|---|---|
| Free tier | 3,000 emails/month (100/day), unlimited contacts, 1 domain — no card required | 1,000 emails/mo (200/day) |
| Entry paid plan | $14/mo — 50,000 emails, unlimited contacts, 10 domains | $15/mo — 10,000 emails (Starter) |
| 100k emails/month | $24/mo (Pro 100k) · $63/mo (Scale, 1000 domains) | Professional from $75/mo |
| Extra volume | $0.90 per 1,000 emails — credits never expire | Per-1,000 overage on subscriptions |
| Transactional + marketing in one | API sends, campaigns, automations, and audiences in every plan | Relay/API focus — no marketing suite |
| Contacts & audiences | Unlimited stored contacts on every plan | No audience management |
| Automations | Included — visual automations, 10,000 runs/month | ✗ |
| A/B testing | ✓ | ✗ |
| Inbound receiving | ✓ | On Professional plan |
| Event webhooks | Signed webhooks: delivered, opened, clicked, bounced, complained, unsubscribed | ✓ |
| Official SDKs | 8 languages + CLI | API + SMTP; limited official SDKs |
| Log retention | 30 days on every plan | 30 days activity on paid plans |
| Dedicated IP | Add-on on Scale — Custom quote | Professional plan |
| INR billing for India | ✓ | ✗ |
SMTP2GO pricing and features summarized from public pricing pages, last checked 2026-08-02. SendDart figures come from the live plan catalog.
Want the row-by-row breakdown? See the full SendDart vs SMTP2GO comparison.
No — SendDart is HTTPS-API-first (REST API, 8 SDK languages, CLI); raw SMTP relay is intentionally not exposed today. If a device or legacy app can only speak SMTP, SMTP2GO is the right tool; if your code can make an HTTPS call, the API is simpler and richer.
SendDart at every published volume: its entry plan undercuts SMTP2GO Starter while including 5× the emails, and its 100k tiers are far below SMTP2GO Professional ($75/month).
It can relay whatever you generate, but there is no campaign composer, audience management, automations, or A/B testing. SendDart includes that entire layer.
It allows 200/day (versus SendDart’s 100/day) but only 1,000/month total versus 3,000. For steady low-volume sending SendDart’s cap is 3× larger.
Replace the SMTP credentials with one HTTPS call — POST /emails with from/to/subject/html — or drop in an SDK. Verify your domain first (guided DKIM/SPF/DMARC), then re-point event webhooks.
Free tier with 3,000 emails a month — API, campaigns, automations, and webhooks included. No card required.