Which values and dates should I document for tax returns that have to be filed after someone dies?

When preparing the return, executors should also review state filing duties, estimated taxes, information returns, and whether prior year returns remain outstanding. When the reporting treatment is determined, a final Form 1040 generally reports income properly attributable to the individual through the date of death, while income received by the estate afterward may belong on Form 1041 if filing thresholds and other requirements are met. Keep the source paperwork rather than relying only on a summary, and let a CPA, enrolled agent, or tax attorney check the reporting party, form, basis, and filing date before the return is submitted.