You can make a 2025 estimated tax payment anytime on or before January 15, 2026. Whether or not you will owe an underpayment penalty when you file your 2025 tax return depends on your total tax payments for the year and when those payments were made in 2025.
Go to this IRS website for information on an underpayment penalty - https://www.irs.gov/payments/underpayment-of-estimated-tax-by-individuals-penalty
