本文以草屯清代找洗契為主，輔以台灣其他地方找洗契，以及中國的找洗契，用來研究找洗契的名稱、格式，找洗的理由、時間、次數、金額等問題。發現草屯的找洗行為和台灣其他地方大致相同，但和中國的找洗習慣逐漸不同。乾隆時，台灣大致沿用中國原鄉舊慣，嘉慶後便不再沿用舊慣，而是產生新習俗新法則。可知嘉慶後，新社會在台灣正逐漸形成。

By the antique contacts of the agreements on additional fees in Tsaotun in the Ching Dynasty assisted with the type of agreements made in other places in Taiwan and China for reference, this paper investigates the titles and formats of the agreements on additional fees, the reasons to make such agreements, the persistence of the agreements, and times of collecting the additional fees. The investigation finds that the agreements made in Tsaotun are generally identical with those made in other places in Taiwan, but the agreements gradually become different from those made in China through time. In the ChenLong Period, immigrants in Taiwan generally made such agreements same as those in their hometowns in China. After the ChiaChing Period, they no longer followed the conventions of making such agreements in their hometowns. They created new rules, which then became the new conventions in the successional periods in Taiwan. By the transition, the fact that the new society was gradually formed in Taiwan after the ChiaChing Period could be proved.