You should report only the amount of property tax you paid during the taxable year. 

If you paid half of your 2024 property tax bill in 2024 and the rest in 2025, you would report the amount paid in 2024 on your 2024 tax return and the amount paid in 2025 on your 2025 tax return.

See IRS  Pub 503

[Edited 04/11/2025|9:04 pm, PST]