It was Twm o'r Nant's custom, having acted an interlude for a time, to have it printed and published in pamphlet form. The interludes which he wrote in his youth have disappeared, but the following have survived: Tri Chydymaith Dyn, Cyfoeth a Thlodi, Cain ac Abel, Pleser a Gofid, Tri Chryfion Byd, Pedair Colofn Gwladwriaeth, Cybydd-dod ac Oferedd, Y Farddoneg Fabilonaidd. These interludes contain a good deal of social criticism. Twm's two main characteristics, his ready wit and his facility in versification, account for many a scathing passage in his works, and also for the fact that some of his verses remained in the popular memory for generations. (It will be recalled how Mari Lewis, in Daniel Owen's novel, Rhys Lewis, was continually quoting ‘Tomos o'r Nant.’) A collection of his poems, entitled Gardd o Gerddi and printed at Trevecka, appeared in 1790. An occasional well-turned couplet in his cywyddau proves that he was conversant with the works of the 15th and 16th cent. poets. He had collected a number of manuscripts, which he sold to William Owen Pughe and which are now at the British Museum.

Twm o'r Nant was a prominent competitor in the early eisteddfodau patronized by the Gwyneddigion Society. In the eisteddfod held at Corwen in May 1789 the adjudicators failed to agree as to who should be given the prize, and the productions of Twm o'r Nant, Jonathan Hughes, and Gwallter Mechain (qq.v.) were submitted for judgement to the Gwyneddigion Society of London, who decided in favour of Gwallter. David Samwel (q.v.), however, favoured Twm, and sent him a silver writing-pen as a consolation prize. Twm was again unsuccessful at the eisteddfod held at Bala in Sept. 1789, but he staged an interlude in the town for a few days after the eisteddfod. In 1790, at S. Asaph, he was given the prize for extempore verse-writing, but won nothing at Denbigh in 1792 or at Caerwys in 1798.