Similarly to TBSAB Et3NSO3 (1) adopts a Gauche conformation within an asymmetric unit cell caused by hydrogen bonding between the methylene hydrogen atoms α to the nitrogen and the oxygens of SO3. The measured N-S bond length in 1 is 1.8720(12) Å c.f. TBSAB N-S formal bond 1.886(3) Å, a comparable bond length to a single N-S bond (typically: 1.73-1.83 Å versus 2.06 Å for a donor-acceptor system) suggesting that 1 exists as a betaine in the solid state which enables the revision of the structure to a formal betaine, termed triethylsulfoammonium betaine (TESAB).