ZIP SIM was a short-term prepaid SIM from Otono Networks of Seattle. It relaunched from Ready SIM in April 2016 and ran on T-Mobile, per a June 2016 review. Its zipsim.com domain is now listed for sale on GoDaddy. BestCellular.com found no official end date.
ZIP SIM appears to be shut down
Otono Networks relaunched Ready SIM as ZIP SIM on April 4, 2016. Users texted a 5-digit ZIP code to get a local number and start a plan. A June 15, 2016 review is the last dated mention BestCellular.com found. On October 14, 2026, zipsim.com redirected to a GoDaddy for-sale listing, and zipsim.us blocked automated reading. BestCellular.com found no official end date.
If you had a ZIP SIM line
No source names a carrier that took ZIP SIM customers. ZIP SIM was built for short trips and assigned a temporary local number, and no source says those numbers could be ported out. If you moved a ZIP SIM number to another carrier, ask that carrier for your account number and port-out PIN.
The T-Mobile network comes from a single 2016 review; the launch release names no carrier. BestCellular.com could not find an official shutdown notice and will update this page if one is published.
How ZIP SIM ended
- April 4, 2016: Otono Networks relaunches Ready SIM as ZIP SIM, a self-activating prepaid SIM for short-term US service.
- June 15, 2016: A kiledjian.com review says ZIP SIM runs on T-Mobile and sells 7 to 30 day plans from $25.
Why ZIP SIM appears to have ended
The sources do not say. The 2016 launch release and review are the last dated mentions. The main domain is now offered for sale, which usually means the brand stopped using it. BestCellular.com found no notice from Otono Networks, no filing and no news report on when or why ZIP SIM stopped selling service.
How to find who holds an old number now
- Check an old bill or payment record. It names the company that billed you last.
- Run the number through a carrier lookup tool. It shows the carrier that holds the number today.
- Call that carrier and ask for the account number and transfer PIN.
- Start the port from the new carrier. Never cancel the old line first.
Your right to keep a number
Number portability is federal law, not a carrier policy. The rule is the FCC’s: Portability: Keeping Your Phone Number When Changing Service Providers.
How we verified ZIP SIM
BestCellular.com tracks active carriers and defunct ones. We keep both, because people still search for brands that no longer exist. Every fact on this page comes from the sources listed below, and we leave a detail out when no source states it. Where sources disagree, this page says so. If you can document a correction, tell us and we will check it against the sources.
Tracked and active are different counts on this site. ZIP SIM counts in our tracked total, not in our active total, so it does not appear in tools built for live carriers.
Questions about ZIP SIM
Is ZIP SIM still in business?
BestCellular.com found no sign it is. The zipsim.com domain is listed for sale on GoDaddy, and the last dated mention of the service is a June 2016 review.
Which network did ZIP SIM use?
T-Mobile, per a June 15, 2016 review on kiledjian.com. The April 2016 launch release from Otono Networks names no carrier, so this rests on one source.
What happened to ZIP SIM customers?
The sources do not say. No successor carrier is named. ZIP SIM sold 7 to 30 day plans with temporary local numbers, and no source says those numbers could be ported out.
How did ZIP SIM work?
You put the SIM in an unlocked phone and texted any 5-digit US ZIP code. The service assigned a local number in that area and started your plan. Plans in 2016 ran 7 to 30 days.
Sources
Checked October 13, 2026.
- GlobeNewswire: Ready SIM Relaunches as ZIP SIM for Instant, Short Term, and Private Wireless Service: Otono Networks of Seattle relaunches Ready SIM as ZIP SIM; ZIP code activation; no carrier named. April 4, 2016.
- kiledjian.com: ZipSIM is a US prepaid: Says ZIP SIM runs on T-Mobile; lists 7 to 30 day plans; domain zipsim.us. June 15, 2016.
- GoDaddy: zipsim.com for sale: zipsim.com redirects to a GoDaddy domain-for-sale listing. Checked October 14, 2026.
Best Cellular. “ZIP SIM: Appears to Be Shut Down,” BestCellular.com. https://bestcellular.com/zip-sim/
Free to reuse with credit. Licence, sources and the full dataset. All defunct carriers are listed on carriers that shut down.
Live carriers to look at instead
No carrier took over ZIP SIM’s customers. These carriers publish their network and run today.