There are 5 13-letter words that start with 'up'.
| upgradability | upperclassman |
| upperclassmen | uprightnesses |
| uptightnesses | |
Note: These 5 13-letter words that start with 'up' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with ups, upr, upt, upb, uph, upp, upg, upc, upl, upd, upw, upf, upe, upm, upa, upk, upo.
3-letter words start with 'up' (2)