Mammoth Uncensored Word List:
17 words ending with es, 22 letters long

adrenoleukodystrophies counterrevolutionaries electroencephalophones encephalomyocarditises episioperineorrhaphies immunohistochemistries incomprehensiblenesses indistinguishabilities keratoconjunctivitides keratoconjunctivitises neocallimastigomycetes philoprogenitivenesses phosphoglyceraldehydes salpingooophorectomies unrepresentativenesses ureterosigmoidostomies vaginoperineorrhaphies