I agree it's a real pain for quarterly estimates until year-end and in some cases close to impossible but taxpayers that use Quicken, Quickbooks, Mint, or even Excel probably could do it except for the major problem with qualified dividends and other tax data they don't have like partnership, s-corp, trust income/lost until year-end. they do have the option of estimating where they don't have full info. but. but if they estimate low they get hit with the penalty after spending time do this every quarter.
