SMTP relay service: keep your software, we deliver the mail
Plug BulkResponse into the app, CRM or email tool you already use. You get SMTP credentials, a monthly credit pool, an hourly ceiling and bounce history. Bulk SMTP relay from $29/month for 50,000 emails.
An SMTP relay service accepts email from your software over SMTP and delivers it for you. BulkResponse gives you a host, port, username and password, plus a monthly credit pool and bounce history. You keep your own sending software. Plans start at $29 a month for 50,000 emails. A relay login does not include campaigns, lists or the email designer.
What is an SMTP relay, and when do you need one?
If your software can already send email but your server cannot deliver it well, a relay fixes the delivery part.
Everything in a BulkResponse relay account
Set up your SMTP relay in three steps
SPF is one copy and paste. DKIM is the step that can take a little longer, and our support team works through it with you.
- Add your sending domainAdd it in your relay account and verify it with the link we email you.
- Publish SPF, and DKIM with our helpOne TXT record for SPF. Adding a domain alerts our support team for DKIM.
- Paste the credentials into your softwareHost, port, username and password. Send a test, then send for real.
How much does a cheap SMTP relay cost?
Five monthly packages. The price per 1,000 falls as you grow.
| Relay credits per month | Price | Per 1,000 | |
|---|---|---|---|
| 50,000 credits | $29/month | $0.58 | Choose |
| 100,000 credits | $49/month | $0.49 | Choose |
| 200,000 credits | $89/month | $0.44 | Choose |
| 500,000 credits Best Deal | $199/month | $0.40 | Choose |
| 750,000 credits | $299/month | $0.40 | Choose |
| 1,000,000 credits | $399/month | $0.40 | Choose |
Monthly credits, not a surprise per-email invoice. Upgrade inside your account at any time.
SMTP relay vs the full BulkResponse Web App
Pick the relay if you already have software. Pick the Web App if you want BulkResponse to be the software.
| SMTP Relay | Web App | |
|---|---|---|
| What you get | SMTP credentials and a credit pool | Full campaign platform |
| Campaigns, lists, designer | No | Yes |
| Autoresponders and triggers | No | Yes |
| Mailbox and SMTP rotation | No | Yes |
| Lead Finder and list cleaning | No | Yes |
| Bounce history | Yes | Yes |
| Starts at | $29/month for 50,000 | $29/month for 25,000 |
Need a dedicated IP or more than a million a month?
Dedicated servers and dedicated IPs are quoted to your daily volume. There is no self-serve IP picker. Tell us your daily number and we price it.
Real reviews from real senders
Quoted word for word from Trustpilot and Capterra, with the reviewer and date. Click through and read every review, including the critical ones.
Ratings read from each site in October 2026. Review counts are shown next to every score.