The work of the assistant tithe commissioners was more diverse and they bore more responsibility than the Local Agent's. They were mainly sent to the Tithe Districts where no voluntary agreement could be reached. A visit of an assistant tithe commissioner had to be advertised in the tithe district 21 days prior to his arrival, outlining the questions he was going to raise and the documents that he would be expecting to see. He heard both sides of the argument, and then proceeded to award a total rent charge on the district.

The rent charge awarded by an assistant tithe commissioner was based upon the average tithe value over the last seven years in that district. In cases where the assistant tithe commissioner perceived the average to be inaccurate, he had the power to impose a higher or lower rate within a 20% margin.

Assistant tithe commissioners also heard appeals against rent charges awarded and litigated disputes against apportionment of the rent charge awarded or agreed upon and the validity of moduses.