What is the maximum amount I can pay using apple pay

In general, you can spend up to the balance available on your card.

That said, unusually large transactions (based on your prior spending history) might well activate a “fraud-protection trip wire.”

If you intend on making any “unusual” purchase, it’s always best to contact your card issuer in advance to discuss.

Some countries impose limits on electronic transactions/payments. Please review the Apple Support article I linked below. Some merchants may set a limit lower than those set by government regulations.

About limits when using Apple Pay in stores – Apple Support