If you keep a prepaid or pay-as-you-go SIM you rarely use, the number behind it is on a clock. Stop using it for long enough and the carrier suspends the line, then recycles the number, then hands it to someone else. (For how that process works, see what happens when you stop using a prepaid SIM.)

The windows are not intuitive and they're not forgiving — they range from about 60 days to over a year depending on the carrier and the country. Below is a country-by-country comparison, each row linked to the carrier's own page or the regulator. Bookmark it.

How to read this. "Number at risk after" is roughly how long with no qualifying activity before your number can be lost — sometimes a suspension window, sometimes a balance/recharge expiry. A CONFIRM tag means the figure comes from a secondary source or the carrier doesn't publish an exact day count, so check it directly before relying on it. Policies change and depend on your exact plan.

United States

CarrierNumber at risk after…Can you get it back?Source (verified Jun 2026)
T-Mobile prepaidUp to 120 days in "Not Paid" status (service stops the day a refill is missed)Refill within the 120 days to keep the number; after that it's cancelled and lostT-Mobile support
Metro by T-Mobile CONFIRMFollows T-Mobile prepaid (~120 days unpaid)Same as T-Mobile; Metro's own terms don't state a day countT-Mobile support
AT&T prepaidBalance expires by amount ($10–24 = 30d, $25–99 = 90d, $100+ = 1yr), then a 60-day grace to payPay within 60 days of balance expiry to keep it; otherwise cancelled and lostAT&T support
Verizon prepaid60 days to renew after the plan ends (accounts from Nov 2018+); older accounts: tiered 30/90/180/365 daysRenew within the window or the number may not be keptVerizon support
Mint Mobile CONFIRM~60 days suspended after a plan lapsesReactivate within ~60 days; then cancelled, balance forfeited, number released (figure from secondary sources)Mint terms
Google FiNo published no-usage cutoff. Pausing keeps your number and auto-resumes after 3 monthsNumber kept during a pause; loss on account closure is handled case-by-case (no fixed figure)Google Fi help
Tracfone / Straight TalkAdd airtime before your Service End Date or the number is lost that day; also after 6 months (smartphones) / 12 months of no usageReactivate within 60 days to recover unused airtime — but you may get a new numberTracfone terms
US MobileCancelled after ~90 days of non-renewalOr pay "Snooze" ($2.98 / 30 days) to hold the number indefinitely; no fixed number-hold window otherwiseUS Mobile terms

United Kingdom

CarrierNumber at risk after…Can you get it back?Source (verified Jun 2026)
EE180 days with no "connection action" (top-up, chargeable call/text, or data)Number + credit lost at disconnection; recovery only via EE, not guaranteedEE PAYG terms (PDF)
Vodafone UK180 days with no chargeable use (reminders at 90 days and 45 days before)Credit lost at disconnection; number quarantined then reissued to someone elseVodafone PAYG terms (PDF)
Three UK180 days with no chargeable activityNo — a disconnected Three PAYG number can't be reconnectedThree support
O26 months with no chargeable activityReconnect only by contacting O2 — and you get a new number, not your old oneO2 PAYG terms
giffgaff6 months with no qualifying use (two warnings sent first)30-day window after deactivation to request a PAC and port the number out; then gonegiffgaff help
Lebara UK CONFIRM90 days no chargeable activity (lose credit); full disconnection after a further ~365 daysTerms reportedly tightened around Aug 2025 — verify the current Lebara terms directlyLebara help
Smarty6 months with no plan purchase / chargeable activity (40-day warning)Suspended first (still receives calls), then terminated; port out before then to keep the numberSmarty terms (PDF)
Lyca Mobile UK CONFIRM90 days no use → notice, then +30 days (~120 days total)Number is reallocated after that; a paid "keep your number" option exists (confirm current price)Lyca FAQ

Australia

CarrierNumber at risk after…Can you get it back?Source (verified Jun 2026)
Telstra PrepaidA 6-month "recharge-only period" after your recharge expiry dateRecharge any time in those 6 months to keep it; after that the number is reallocatedTelstra prepaid terms (PDF)
Optus Prepaid186 days (~6 months) from your credit expiry dateRecharge before day 186 to keep the number; otherwise disconnected and lostOptus prepaid CIS (PDF)
Vodafone AU Prepaid120 days with no recharge (from last recharge expiry)Then disconnected; number quarantined 6 months, during which Vodafone may reconnect itVodafone AU support
Boost Mobile (AU)6 months with no recharge (Telstra network/terms)Recharge within the 6-month recharge-only period; after that the number is reallocatedBoost help
amaysim365-day active period + a 90-day passive period (~455 days total)Recharge before the passive period ends; after that the service (and number) is cancelledamaysim service description (PDF)
ALDI Mobile365-day credit validity + a 120-day "additional period"Recharge within the 120-day window; otherwise the service is cancelled and the number lostALDI Mobile terms (PDF)

Canada

CarrierNumber at risk after…Can you get it back?Source (verified Jun 2026)
Rogers (Pay As You Go)Balance at $0 for 6 consecutive monthsKeep a positive balance / top up before then; after deactivation the number is releasedRogers Terms of Service
Fido prepaidBalance at $0 for 6 consecutive monthsTop up before then; after deactivation the number is releasedFido Terms of Service (PDF)
Bell prepaid90 consecutive days with no paymentTop up before 90 days; otherwise auto-cancelled, balance lost, number releasedBell support
Lucky MobileSuspended on the charge date if underfunded; deactivated after 4 consecutive monthsPay before the 4 months end; after deactivation you get a new number, not your old oneLucky Mobile support
Telus (Pay As You Go)90 days with a zero balance (7-day carry-over for credits)Keep a balance / auto-renewing plan; otherwise auto-deactivated and the number lostTELUS service terms (PDF)
Koodo90 days without an active base plan (58 days for new activations)No — service is cancelled, the account permanently deactivated, and the number lostKoodo service terms
Public MobileSuspended if you can't renew; 90+ days suspended → permanently closedReinstate any time within 90 days; on day 91 the number is lost and can't be portedPublic Mobile terms (PDF)
ChatrNew accounts: inactive on day 58; existing: balance below the monthly fee for 3 consecutive monthsKeep the balance at/above the monthly fee; after deactivation a new SIM and new number are requiredchatr terms (PDF)

What the regulators actually require

The day-to-day window is set by your carrier, not the regulator. But regulators do govern what happens to a number after it's disconnected:

  • US (FCC): a disconnected number must be "aged" at least 45 days before reassignment (residential numbers up to 90 days, business up to 365). 47 CFR § 52.15
  • UK (Ofcom): no single mandated period. It's "use it or lose it," providers set their own windows (commonly ~90 days to 12 months) and should warn you first. Ofcom guidance
  • Australia (ACMA): a disconnected number is quarantined for 6 months before it can be reissued (12 months if disconnected for nuisance calls). ACMA
  • Canada (CRTC): disconnected numbers are aged up to about 2 months for residential landlines, about 3 months for wireless, and about 6 months for business landlines before reassignment. CRTC / CSCN numbering guidelines

What counts as "activity"

Across almost every carrier above, the rule is the same: it has to be something the carrier bills.

  • Usually counts: an outgoing billable call or SMS, paid mobile data on the carrier network, or a top-up / paid add-on.
  • Usually doesn't count: WhatsApp, iMessage, FaceTime and other internet apps — they run over data and never touch carrier billing. Incoming calls, texts, and voicemail often don't count either.

So the cheapest way to keep a number is one small billable action before the window closes — more on that in how to keep a prepaid SIM active without spending money.

Stop tracking this in your head

Different carriers, different windows, none of them forgiving. KeepSim turns each row above into a per-SIM countdown, warns you before the deadline, and lets you fire a keep-alive action in one tap. Local-first, no account.

Get KeepSim on the App Store

Common questions

Which prepaid carrier holds your number the longest?

The longest runways come from long-validity plans — e.g. amaysim (~365 days active + 90-day passive) and ALDI Mobile (365 + 120 days) in Australia. Most US and UK prepaid lines are shorter, often 60–180 days. Confirm your own plan.

Does a regulator decide how long before my number is recycled?

Not the day-to-day window. The US FCC sets a 45-day minimum aging before reassignment; Ofcom sets none; Australia requires a 6-month quarantine; Canada ages residential landlines up to ~2 months, wireless up to ~3 months, and business landlines up to ~6 months. The window before your line is disconnected is set by your carrier.

What counts as activity to keep a prepaid number?

Generally a billable action: an outgoing call or SMS, paid mobile data, or a top-up. WhatsApp/iMessage/FaceTime run over data and usually don't count. Incoming calls and voicemail often don't either.

Last verified June 2026 against the source linked in each row. Carrier policies change frequently and depend on your exact plan, account age, and country — treat this table as a starting point, not legal advice, and confirm the current rule with your carrier before relying on it. Rows tagged CONFIRM come from secondary sources or carriers that don't publish an exact day count. KeepSim is a personal reminder tool; it does not provide telecom service or keep numbers active on your behalf.