There is no mention in any of the editions of Pevsner of a gildhall in Withersfield.

There is a house named the Guildhall in Withersfield which is shown under that name in the Historic England building listings, here. The text does not mention any use as a guildhall but it does say it is "a C17 timber-framed house", which is well after the Reformation (dissolution of the monasteries and gilds).

There was a gild in the village (see below). I cannot find any other supporting evidence at the moment. At best this was rebuilt on the site of an older building but all we have to go on is the house name.
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The extract(s) below are taken from one or more of the following articles in PSIAH (see the Sources page for details of how to access).

Morley, C., 1926, A check-list of the sacred buildings of Suffolk, to which are added Gilds. XIX Part 2, 168-211.

Redstone, V. B., 1904, Chapels, Chantries and Gilds in Suffolk. XII Part 1, 1-87. Has abstracts of 39 gild certificates, 18 in Bury (presumably the 1389 returns). Also details of Ipswich Corpus Christi gild.

Redstone, V. B., 1937. IV. Extracts from wills and other material, showing the history of Suffolk churches, chantries and guilds (Appendix to article published in Proceedings Vol XII). XXIII Part 1, 50-78.
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