Do recommenders get a grace period to submit their LORs after the deadline?

Hi, I wanted know if it is allowed for recommenders to submit their letters after the application deadline? I’m a bit panicked right now because I’ve had some personal stress recently, and I’m having to finish my applications at the last minute. Do recommenders generally get a grace period to submit, or do they also have to meet the exact deadline? I just want to make sure I’m not wasting time if the letters won’t be accepted after the deadline.