GTBank started this buying credit from your account first, i think. I received an email from GTBank some time ago stating how you can load credit with your GTBank account no matter the network provider. So, i tried it and viola, it worked! I was happy because this new innovation just made me lazier, ever since i started using GTB Top Up Service i haven’t gone out to buy credit from a local vendor when all i should do is simply dial a code and viola, credit gets sent directly to my phone, easy. No stress!
So, all your have to do is Dial *737*TheAmount# Example *737*200# and press send. You can buy as much as N5,000 and as low as N50.
If you have an Ecobank Account, You can also buy credit from your Ecobank account, like this,Read this How To Load Credit With Your Ecobank Account