What is the penalty for failing to file a partnership tax return by the due date, including extensions?

The penalty for failing to file a partnership tax return by the due date, including extensions, is indeed $210 per month or part of a month for each partner, with a maximum duration of 12 months. This means if the tax return remains unfiled, the penalty can accumulate based on the number of partners in the partnership and the number of months the return is overdue, reaching a substantial total if not rectified within that timeframe.

This approach encourages compliance with tax filing responsibilities by imposing a significant financial penalty for delays, thereby emphasizing the importance of timely submissions in accordance with IRS regulations. The structure of the penalty ensures that partnerships understand the necessity of maintaining accurate and timely records to avoid potential financial repercussions.

In distinguishing this correct choice from others, it is relevant to note that the maximum penalty periods specified in the incorrect options, which are shorter than 12 months, do not align with IRS guidelines regarding the filing of partnership returns.