How many letters does the top answer for “showing a cheerful willingness to do favors for others” have?

The most common answer is complaisant (11 letters).

Crossword clue: showing a cheerful willingness to do favors for others

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

complaisant 11 letters wn-def

showing a cheerful willingness to do favors for others

obliging 8 letters wn-def

showing a cheerful willingness to do favors for others