Synonyms of at once

at once

phrase

1

as in concurrently

at one and the same time

I have three papers due all at once.

Synonyms & Similar Words

• concurrently
• simultaneously
• together
• coincidently
• in unison
• immediately
• contemporaneously
• coincidentally
• near
• close
• narrowly

Antonyms & Near Antonyms

• separately
• apart
• independently
• individually
• singly
• successively
• consecutively

2

as in now

without delay

Call me at once when you get this message.

Synonyms & Similar Words

• now
• immediately
• directly
• promptly
• instantly
• right
• right now
• soon
• shortly
• right off
• suddenly
• right away
• presently
• in no time
• on the spot
• away
• straight off
• quickly
• on the double
• forthwith
• headlong
• on a dime
• instantaneously
• straightway
• straightaway
• PDQ
• incontinently
• off the bat
• momentarily
• abruptly
• plumb
• pronto
• rapidly
• quick
• bang
• instanter
• freely
• swiftly
• readily
• swift
• hastily
• fast
• unexpectedly
• speedily
• briskly
• apace
• anon
• exactly
• recklessly
• impetuously
• fleetly
• rashly
• impulsively
• snappily
• presto
• full-tilt
• punctually
• posthaste
• opportunely
• seasonably

Antonyms & Near Antonyms

• slowly
• late
• tardily

Example Sentences

Recent Examples of at once

Rather than focusing exclusively on protein, the future food world could encapsulate multiple nutrients at once—such as by creating meals that are both high-protein and high-fiber. — Sophia Beams, Better Homes & Gardens, 23 July 2026

Suarez says the zoning plan would address several problems at once. — Andres Viglucci, Miami Herald, 22 July 2026

Increasingly, insured Americans are navigating more than one healthcare market at once. — Deidre Popovich, The Conversation, 22 July 2026

Air defenses may have to detect, track, prioritize, and engage dozens of incoming objects at once. — Atharva Gosavi, Interesting Engineering, 21 July 2026