How to Unlock iPhone 3G or 3GS running iOS 4.0 using Ultrasn0w

Yesterday we showed you how to Jailbreak your iPhone 3g running iOS 4.0 using the RedSn0w app on Windows. Hot on the heels of the jailbreak here’s a very quick but immensely helpful unlock solution for you.

This guide has actually been tested on the said devices and works like a charm. The unlock via Ultrasn0w will work on both your iPhone 3G and iPhone 3GS with almost any baseband. However do make sure that your baseband is one of the following:

Go to Settings > General > About > Modem Firmware to get this info.

  • 04.26.08
  • 05.11.07
  • 05.12.01
  • 05.13.04

In case your baseband is present in the list above, proceed with these instructions once you have jailbroken your iPhone.


Launch Cydia. Click on Manage tab and then on Sources. Click on the Repo that reads “”. If its not present click on Edit and then Add. Type the URL without quotes.



Click on Ultrasn0w and then on the Install button. Make sure you have a working wifi or data connection before you click on Confirm as Cydia will download the app.




Voila! That’s it. Now reboot your phone and while it restarts you may put in any other sim card other than the carrier the phone was locked to. For instance, I tried a BSNL sim on my iPhone 3G that was locked to Airtel. It worked the first time and without any issues. The network search is pretty fast and takes around 15 seconds maximum to register network.

Go ahead and unlock your iPhone. Let us know if you run into any issues. We might be able to lend a helping hand as always.

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