There are a total of 589 6-letter words starting with the letter 'u', and the number may vary in different dictionaries. You can specify the dictionary and order.

• united ₉
• unless ₉
• useful ₁₂
• unable ₁₂
• unique ₁₈
• unions ₉
• unlike ₁₃
• upward ₁₄
• unfair ₁₁
• unpaid ₁₂
• update ₁₁
• urgent ₁₀
• utmost ₁₀
• unjust ₁₈
• uterus ₈
• urging ₁₂
• upheld ₁₄
• uptake ₁₄
• unduly ₁₃
• unused ₁₀
• usable ₁₁
• unsafe ₁₁
• upland ₁₃
• uneven ₁₃
• uneasy ₁₀
• unseen ₉
• unrest ₈
• ulcers ₁₁
• unwise ₁₁
• uphold ₁₄
• upside ₁₁
• uplift ₁₄
• untrue ₉
• ulster ₈
• unison ₉
• usages ₉
• unfold ₁₃
• utopia ₁₀
• unites ₈
• unload ₁₀
• undone ₁₀
• unsure ₉
• unborn ₁₂
• unreal ₉
• upkeep ₁₇
• ureter ₇
• untold ₁₀
• umpire ₁₃
• uncles ₁₂
• unsold ₁₀
• uproar ₁₀
• unruly ₁₂
• uphill ₁₄
• unlock ₁₆
• unkind ₁₄
• uptown ₁₄
• unholy ₁₃
• ultimo ₁₁
• urchin ₁₃
• utters ₇
• untied ₉
• upsets ₁₀
• upshot ₁₂
• uremia ₁₀
• unwary ₁₃
• uranyl ₁₁
• ushers ₉
• upbeat ₁₃
• upturn ₁₂
• unease ₈
• untidy ₁₁
• upload ₁₂
• unwell ₁₃
• uremic ₁₃
• urbane ₁₁
• upwind ₁₅
• unpack ₁₈
• unwind ₁₃
• unripe ₁₁
• uppers ₁₃
• unhurt ₁₁
• uplink ₁₆
• unsaid ₉
• uracil ₁₁
• unveil ₁₃
• unsung ₁₂
• uproot ₁₀
• urinal ₉
• unread ₉
• ultima ₁₁
• urease ₇
• urania ₈
• unmade ₁₂
• udders ₉
• unmask ₁₅
• unseat ₈
• undead ₁₀
• urines ₈
• undine ₁₀
• usurer ₈
• unfree ₁₁
• unroll ₁₀
• uglier ₁₀
• ubuntu ₁₃
• umbels ₁₄
• urates ₇
• unwrap ₁₄
• usurps ₁₁
• unplug ₁₅
• upflow ₁₇
• unisex ₁₅
• unfurl ₁₃
• undoes ₉
• uptime ₁₃
• unmake ₁₅
• unicom ₁₄
• unfelt ₁₂
• uppity ₁₅
• uronic ₁₁
• unbent ₁₂
• uropod ₁₁
• unworn ₁₂
• upping ₁₆
• umlaut ₁₂
• uncial ₁₂
• undyed ₁₂
• unhook ₁₄
• umwelt ₁₁
• ultras ₈
• unfits ₁₁
• unbend ₁₃
• unshed ₁₁
• ullage ₁₁
• unself ₉
• ujamaa ₁₉
• unbind ₁₃
• unmold ₁₃
• uptick ₁₇
• unties ₈
• urtica ₈
• uncoil ₁₂
• ubique ₂₀
• unhewn ₁₄
• unshod ₁₁
• umbers ₁₃
• unseal ₉
• uprose ₁₀
• unclad ₁₃
• undies ₉
• unguis ₁₁
• upcast ₁₃
• unlade ₁₀
• unkept ₁₅
• ungual ₁₂
• unbolt ₁₂
• unaged ₁₁
• uncool ₁₂
• utiles ₈
• umbral ₁₄
• uhlans ₁₁
• unwept ₁₄
• unawed ₁₂
• unking ₁₅
• untrod ₉
• uglies ₁₀
• unital ₆
• unlink ₁₄
• uprush ₁₃
• urning ₁₁
• uprise ₁₀
• unmeet ₁₁
• uncork ₁₅
• uvular ₁₃
• usance ₁₁
• unspun ₁₃
• unhand ₁₂
• unlace ₁₂
• uraeus ₈
• unclog ₁₄
• utopic ₁₃

There are 589 6-letter words starting with the letter u in the well-known word game dictionary, in the Scrabble US (US/Canada/Thailand - TWL/NWL) dictionary, and in the Scrabble UK (International - SOWPODS/CSW) dictionary, and in the Words with Friends (WWF) dictionary.