Who bears the cost when the final tax bill far exceeds the executor's reserved funds?

Summary

The executor withheld funds for taxes and fees, but after distribution the tax charge exceeded these amounts. Who ultimately must cover the extra tax liability?

so the extra tax comes out of the estate assets, not the executor’s pocket. if the funds fall short, the heirs bear the reduced leftover, not a direct cost on the executor.

I believe any extra tax liability is charged to the estate, right? It seems tricky when distributions shrink because of unforeseen deficits. How might one better manage those risks upfront?