# SMS-receiving number (disposable number)

An SMS-receiving number is one a public website publishes so anyone can read the texts sent to it, verification codes included. Spaw matches two open lists daily.

Date: 2026-09-27

An SMS-receiving number, often called a disposable or temporary phone number, is a number that a public website publishes so that anyone can read the text messages sent to it. A verification code sent there can be read by whoever opens the page, so the number proves nothing about the person who typed it.

## What Spaw answers

Spaw merges two open lists of such numbers, from iP.1 Networks and Castle (both MIT), every day. `is_disposable` is true when the merged table holds the number, whether a list carries it today or every list has dropped it and it was last seen within the last 730 days, and `disposable_seen_at` gives the date it was last seen. Three signals follow from the listing:

| Signal | When | Weight |
| --- | --- | ---: |
| [`disposable`](/docs/signals/phone/disposable) | Listed and seen within the last 365 days (an undated listing counts as fresh), or dropped by every list and seen within the last 90 days | +70 |
| [`disposable_stale`](/docs/signals/phone/disposable_stale) | Listed or dropped, but not seen inside those windows; a dropped number is kept at its last-seen date for 730 days | +40 |
| [`disposable_range`](/docs/signals/phone/disposable_range) | Not listed itself, but in a 1,000-number range holding 10 or more listings that still score `disposable`; `is_disposable` stays false | +30 |

`disposable` is one of the default block signals of the [SMS policy](/glossary/sms-policy), so a fresh listing answers `ok_to_send: false` with `blocked_by: "disposable"`. The other two pass the defaults on their own, because +40 and +30 are within the ceiling of 60. The test numbers show both ends: +1 202 555 0103 answers `is_disposable: true`, a score of 70 and `blocked_by: "disposable"`; +1 202 555 0113 answers `disposable_range`, a score of 30 and `ok_to_send: true`.

## What the lists hold

The two lists synced on 24 September 2026 held 128,030 numbers under 103 calling codes. North American numbers were the largest group, 35,988 (28.1%), followed by +44 with 15,877 (12.4%) and +86 with 13,130 (10.3%). Most listings are old: on 27 September 2026, 18,934 of them (14.8%) were fresh enough to score `disposable`, and the rest scored `disposable_stale`. Of the 25,659 listed numbers with a US area code, at least 64.7% sit in blocks whose holders are on Spaw's classification list of [virtual-number](/glossary/virtual-number) wholesalers and VoIP providers (the holder the block was allocated to, not who serves the number today), against at least 19.7% of all allocated US numbers in NANPA's tables of 26 September 2026. The full table by calling code is on the [phone statistics](/statistics/phone) page.

## What it does not mean

A listing says a website published the number on a date. It says nothing about who holds the number today: the sites give numbers up, and a carrier can issue one to a subscriber who never saw the site, which is why the weight drops once a listing is stale.

`is_disposable: false` means not listed, not safe. Many SMS-receiving numbers are never scraped into a list; `disposable_range` covers only the unlisted neighbours of listed numbers, and a real subscriber can hold a number beside a run of rented ones.

The lists name no owner and neither does Spaw: there is no reverse lookup and no caller name in any answer.

Reference: https://spaw.co/glossary/sms-receiving-number