25% of withholding is deemed paid each period but by checking box D on the 2210 you can use actual withholding for each period.
timely estimates are based on the dates you entered in the tax payments worksheet, bad dates or late payments would result in penalties being calculated. you need to check those dates and review the 2210 to see what periods are subject to penalty and what's being used for tax payments. This forum has no access to your return.
