I support everything said here already but also think about the asymmetry of information. Per chollida1's comment, you'r manager didn't go to bat for you....why

I support everything said here already but also think about the asymmetry of information. Per chollida1's comment, you'r manager didn't go to bat for you....why? Your current manager obviously knows more about you than your future company so he/she is probably better at estimating your true worth than your future employer. Also...hassle. Given your contribution vs how much work it would be to get you a 30% raise, your manager maybe decided they couldn't do it or it wasn't worth sticking out their neck for it. However, if you want raises, it's usually always better to switch employers. It's the fastest path to more money.