No hot water in bathroom sink

When I turn on the hot water faucet in the bathroom sink, there is no water coming out of the faucet. The cold water works fine, as does the hot water in the shower and the kitchen. Do you have any idea what might be wrong? By the way, the hot water valve is turned on.

You may have some crud in the hw stop valve. Did you recently turn that valve off for any reason?

In any case, you'll need to unscrew the hw supply line from it and try to flush it out, by shooting the water into a bucket. If no water comes out, you'll need to remove the stop valve and clean it or replace it.

It's also possible that your hot supply line is kinked or that the hw valve in your faucet is plugged.

Is the faucet a single or double-handled job? It could be clogged anywhere from the shut-off in the wall to the valve at the faucet. It's not the aereator, since cold comes out. Could also be a bad hose.

I have not recently turned off the hot water valve. It was working fine one day and then the next day there was no water. Thank you for your reply.

It is a double-handled faucet.

You probably have some small piece of scale or debris from the water heater that clogged the hot water shut-off valve or the hot side of the faucet.
Turn the cold water supply valve to the water heater OFF (which will cut-off the hot water only), and remove the handle cap of the hot water shut-off valve. (Turn OFF the main shut-off valve if you don't have one on the water heater.) Put a towel over it, and have someone open that cold water valve very briefly to flush it out.
If that doesn't do it, do the same for the hot faucet handle to flush it.
Good luck!
Mike