When I got onto my 5 GB plan, I had safety mode enabled to turn on automatically. But this month, It says on Details under Data Hub on the Verizon app (I haven't found an equivalent page in the browser) that I have used 5.1 GB. When I was signed on, I was told that when safety mode was enalbed, loading of anything would become very slow (apparently also you should get charged at a lesser rate because of it, but that's stuff I have heard people say on forums has happened to them, not from a sales rep). But when I went over, loading did not slow at all. I also found this page in the FAQ's that says if you go over at all, you are charged "No matter what size data plan you have, all overages are billed at $15 for each 1 GB, rounded up. For example, if you use 250 MB over your allowance, you'll be charged $15." If that is true, then it makes safety mode useless unless it turns on before you go over anyway.
Overages are simple.
If you have a current data plan with safety mode turned on, your data runs at 4G speed within limit - 2G speed when over. No overage charge in this scenario.
If you go over even the smallest amount without safety mode, it's a $15 charge. Doesn't matter if you used 5.01GB of data or exactly 6GB, it's treated as a 1GB overage.
Dear snezling, if you have a tiered data plan with Safety Mode enabled, you will not receive any overages. Please let us know if you are unsure of what plan you have, or if Safety Mode is, indeed, active on your account.