Does iOS6.1.3 use massive amounts of data?

I have an iPhone 4s on iOS6.1.3. I have been given an iPhone 4 running iOS4 something… I'm not sure if upgrading it to iOS6 will take massive amounts of internet data. It doesn't matter on the one i have now because I have unlimited internet but my other contract only has 500mb of internet per month and I don't want to go over that… Will iOS6 make it go over?

Its not the operating system that does that. Its the apps you use & how long you use them while on a 3G/4G connection.

If you connect your iPhone 4 to your home Wi-Fi (or a public Wi-Fi hotspot) while downloading and installing the update, it will only use the home/public Wi-Fi data, which will not come out of your mobile allowance.

Alternatively, you can connect the phone to your computer via usb, and update that way. That will also use your home internet.