There are a few ways that you can save 20% on airtime plans. Signing up to O2 Multisave is one way, offering 20% off every new airtime plan you add to your account. Additionally, using an O2 promo code is another great way to save, and can be found throughout the year on our page. These deals and offers are tested by a member of our team, to ensure they are valid and working. Finally, exploring any ongoing O2 sales that are happening is another great way to save on your airtime plan - you could even get discounts on other O2 products too, including accessories and contract add-ons.