DoninGA didn't actually answer the question. An estimated tax payment made now (for Q4) will not correct any underpayment for Q1 through Q3 (although it can limit the continued accrual of penalty and interest for Q1 through Q3 from the payment date forward). At this point, correcting for underpayment in Q1 through Q3 can only be done via tax withholding, 1/4 of which would be applied to each of the tax quarters, not by estimated tax payment. Unlike tax withholding, estimated tax payments are only credited when actually paid.
If the largest portion of your income occurred in Q4, annualizing income on Schedule AI of Form 2210 will reduce or eliminate the underpayment for earlier quarters. Otherwise, income and tax withholding are treated by default as having been received and paid evenly throughout the year.
