# Free Transactional Email API (6,000 a Month, Forever)

> SadaSend gives developers 6,000 free transactional emails a month, every month, with a 200-a-day burst safeguard and no credit card required. Unlike the 30-day trials that expire before an app ships, this one does not end — the counter resets on the same day each month and the free tier includes every guardrail and all ten MCP tools.

## Competitor Free Tier Comparison

| Provider | Free Quota | Daily Cap | Expiration | Credit Card? | Sandbox Hold |
| --- | --- | --- | --- | --- | --- |
| SadaSend | 6,000 emails / mo | 200 / day | Never expires (renews monthly) | No | Zero sandbox (Instant live) |
| Resend | 6,000 emails | 100 emails / day | Monthly reset | No | Domain verification only |
| Twilio SendGrid | 100 emails / day | 100 emails / day | Trial expires / KYC hold | Yes (Automated hold) | Strict KYC review |
| Mailgun | 0 emails (Trial only) | Varies | Expires in 30 days | Yes | Authorized recipients only |
| Amazon SES | Sandbox mode only | 200 emails / day | N/A | Yes (AWS Account) | 3-day manual support ticket |

## 60-Second cURL Quickstart

```bash
curl -X POST https://api.sadasend.com/v1/emails \
  -H "Authorization: Bearer YOUR_SADASEND_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "auth@yourdomain.com",
    "to": "developer@example.com",
    "subject": "Your First Transactional Email",
    "html": "<p>Dispatched in <strong>18ms</strong> via SadaSend Free Tier.</p>"
  }'
```

## What is Included in the Free Tier

### 6,000 Free Sends Every Month (Renews Forever)

Unlike competitor trials that expire after 30 days, your 6,000 emails renew automatically every month with a 200-a-day burst safeguard. Perfect for MVP development, production side projects, and continuous staging verification.

### Pre-Flight Recipient Validation

Every email sent on the free tier is automatically pre-validated for correct RFC syntax, MX record presence, and disposable burner domain detection before dispatch, protecting your sender score.

### Zero Sandbox Hold

No 3-day AWS support bureaucracy or manual KYC approval delays. Once you verify your domain DNS records (SPF, DKIM, DMARC), you can immediately dispatch to any real recipient address.

### Per-Key Recipient Allowlists

Scope staging and development keys to only send to your team’s addresses (e.g. *@yourcompany.com). Even on the free tier, your local code is physically barred from leaking to external users.

### Native Model Context Protocol (MCP) Server

Connect Claude Desktop, Cursor, or Windsurf AI agents directly to your SadaSend account with 10 native tools and hardware-enforced spending limits.

### Dead-Letter Queue (DLQ) & 30-Day Logs

Full delivery status observability with 30 days of searchable event logs and built-in message capture so you can replay failed webhook deliveries with a single click.

## Frequently Asked Questions

### Do the 6,000 free emails really never expire?

The free tier itself never expires — you get 6,000 emails a month, every month, for as long as the account exists. The monthly counter does reset, so an unused balance is not banked: send 10 in development and you have 6,000 again next month, not 11,990. There is also a 200-a-day burst cap, which is a rolling 24-hour window rather than a calendar day, so a quiet month followed by a launch spike is paced rather than refused outright.

### Do I need to enter a credit card to use the free tier?

No. You can sign up with GitHub or Google OAuth, generate your API key, and begin sending test emails immediately without entering a credit card.

### What happens when I use up my 6,000 free emails?

When your quota is reached, dispatch halts safely without surprise overage charges. You can upgrade anytime to the Starter plan ($12/month for 15,000 emails), Pro ($19/month for 75,000 emails), or Scale ($79/month for 250,000 emails).

### Can I use custom domains on the free tier?

Yes. You can add up to 3 custom sending domains, configure standard DNS records (SPF, DKIM, DMARC), and send branded emails from your own domain addresses with zero SadaSend watermarks.

### Can I send via both REST API and SMTP relay on the free tier?

Yes. Your free account includes full access to both the HTTPS REST API (https://api.sadasend.com/v1/emails) and our standard SMTP relay (smtp.sadasend.com:587 with STARTTLS).