Resident Tax (Leaving by 2/1)

Despite reading tons of articles, I find myself confuse on how much tax I owe to the gov't.

I worked for nearly 8 years and will be leaving by 2/1.

Since I have remaining leaves, they will be used until 2/28. Therefore, I will receive both January and February salaries this month.

For the Resident Tax, I will have to pay ~10% of my 2025 income.

Which means that if my income is 2.5M for 2025,

– I have to pay up to 250,000 yen? Is my understanding correct?

– Or is it the 10% of the total resident tax of 2025 (small amount)

– Lastly, is the deduction based on Gross or Net Income?

Thanks!