Key Takeaways
- Free SMS server delivery reports are the same DLR path as paid — a status about a PDU from your SIM, not a CPaaS POP.
- Do not rewrite the DLR product page or the free-server hub. This spoke is free-tier limits on reports.
- Free is 300 SMS lifetime / 1 device. You cannot soak-test DLR on the free SKU.
- Accepted HTTP is not delivered. Doze delays the callback.
- You bring operator credit. We do not sell airtime.
- Demo footers may ride on trial SMS — do not treat those as production templates.
Free DLR is still radio truth
Free SMS server delivery reports are how you learn whether a PDU left the SIM you funded — on a free control-plane tier that still caps volume. “Free” does not mean fake DLR, and it does not mean 10,000 test messages. It means 300 lifetime SMS on this product’s Free SKU, 1 device, your airtime.
Hub J: free SMS server. Product DLR: delivery reports. Phone-path in-depth: phone as gateway DLR— do not clone those here.
“If you burned the 300 on load-test DLR, you learned the cap, not production.”
Use the free-server hub
What free includes, trial footers, and upgrade triggers live on hub spokes. Live webhook/DLR fields: Developer Center.
What a DLR is not
| People say | Reality on a free SIM path |
|---|---|
| API 200 = delivered | Accepted only |
| Missing DLR = API outage | Often Doze or webhook TLS |
| Free DLR is a paid extra | Status exists; volume is capped |
| Failed DLR returns airtime | Operator keeps the segment; we don’t cash out packs |
| Blended DLR across SIMs | Lies — segment by device |
Webhooks: best practices, HTTPS.
300 lifetime is a bad load test
Free: 1 device, 300 SMS lifetime, 300 contacts — then pause. Developer is 25,000/year still on 1 device. Soak DLR on a paid SKU or you will pause mid-test. What free really includes.
HTTPS + HMAC
Same rules as paid. HTTP staging is how you donate forged DLR. Webhook guide.
Cost
Operator segments still bill on failed and delivered. Platform volume meters on send. Pause on Free when the 300 is gone. Pricing.
Checklist
- Hub + /dlr read; this page is free-tier DLR only.
- Canary DLR on a staff phone, not 300 randoms.
- Webhook HMAC in staging.
- Doze distinguished from missing callback.
Next steps
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- SMS delivery reports (DLR)Delivery status tracking
- device and SMS volume pricingPlans and allowances
- Android SMS gateway product guideDefinition, product, and how to buy
- SMS API documentationLive endpoint reference
