1 B1 neutral
To accumulate or be arranged in a growing pile
"The unread emails were stacking up while she was away on holiday."
inseparable
stack up
B2 neutral separable transitive/intransitive
To accumulate in a pile, or to compare favourably or unfavourably with something else
In plain English
To build up in a pile, or to see how good something is compared to something else
What does "stack up" mean?
3 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic neutral
To compare with someone or something else in terms of quality, performance, or merit
"How does the new model stack up against last year's version?"
inseparable
3 B2 idiomatic informal
To make sense or to be logically consistent (chiefly American English)
"His alibi doesn't stack up — three different witnesses contradict his story."
inseparable
Literal vs figurative
Words literally mean
To place items one on top of another, forming a stack
Actually means
To build up in a pile, or to see how good something is compared to something else
Usage tip
Has a clear literal sense (physically stacking things) and a very common figurative sense meaning to compare. 'How does X stack up against Y?' is a very common construction. Also used to mean 'to make sense' or 'to be consistent' in American English ('the numbers don't stack up').
Words that pair with "stack up"
Natural word combinations native speakers use most often.
competition rivals comparison evidence costs problems
How to conjugate "stack up"
The five tense forms you'll use most often.
Base
stack up
I/you/we/they
3rd person
stacks up
he/she/it
Past simple
stacked up
yesterday
Past participle
stacked up
have + pp
-ing form
stacking up
continuous
Hear "stack up" in the wild
Listen to native speakers using "stack up" in real YouTube videos — click a clip to watch it on Looplines.
Other ways to say "stack up"
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Keep exploring
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