# OPS-090 — Check the number is a live mobile before paying to send to it

> Destination numbers should be validated as real, active mobile numbers before sending, since platforms bill accepted requests regardless of delivery.

- **Rule ID:** OPS-090
- **Layer:** Operational (`OPERATIONAL`)
- **Checks:** `destination number validation`
- **Severity:** MEDIUM — Usually survives review, but lowers your trust score or invites manual review.
- **When it bites:** Falls due after approval, once you are live and sending
- **How it is detected:** External record we cannot query — reported as a warning to verify
- **Fix type:** Wait on an external system or a required interval
- **Required by:** AWS
- **Applies:** Applies to every 10DLC registration.
- **Canonical URL:** https://ekas.io/rules/10dlc/operational/ops-090/

## Why this rule exists

Billing happens on acceptance, not delivery, so a list full of landlines, disconnected numbers and typos costs money on every send and returns nothing. It is also a quality signal the carriers read: a high proportion of invalid destinations is one of the shapes that distinguishes a purchased list from an organic one, so the waste and the reputational damage arrive together.

## How to fix it

Run a lookup against the list before a large send and drop landlines, invalid formats and disconnected numbers. Done when the invalid rate on a send is measured rather than assumed.

## Example of a compliant value

```text
Pre-send lookup: 40,000 numbers → 38,900 mobile, 700 landline, 400 invalid → send to 38,900.
```

## Check this yourself

**Is the invalid rate on your sends measured, rather than assumed?**

1. Run a lookup against the list before a large send and drop landlines, invalid formats and disconnected numbers.
2. Weigh the per-number lookup cost against the per-message cost of sending to numbers that cannot receive — for a list built from typed-in phone fields it usually pays for itself on the first send.

*What wrong looks like:* Billing happens on acceptance, not delivery, so the waste is invisible in the delivery metrics. A high proportion of invalid destinations is also one of the shapes that distinguishes a purchased list from an organic one.

## Notes

A paid per-number lookup at the provider. What the user has to weigh is the lookup cost against the per-message cost of sending to numbers that cannot receive — for a list built from typed-in phone fields the lookup usually pays for itself on the first send.