Mom vs Mum

When to use each in English, with meaning, register, and examples.

Mom

Top 1,000 (very common)B1noun

Mum

InformalTop 1,000 (very common)A1noun
Most formal: Mom
 MomMum
Pronunciation🇬🇧 /["/mɒm/"]/🇺🇸 /["/mɑːm/"]/🇬🇧 /["/mʌm/"]/🇺🇸 /["/mʌm/"]/
MeaningA female parent or mother.A word for mother.
ExampleWhere's my mom?Mum is making dinner for the whole family.
RegisterNeutralInformal
How commonTop 1,000 (very common)Top 1,000 (very common)
CEFR levelB1A1
Part of speechnounnoun
Collocationsmom and dad, stay-at-home mom, mom's advice, mom's cooking, single momyoung, single, unmarried, mum and dad
Antonymsdaddad, father
Common mistakesConfused with 'mum' in British English., Using 'mom' in very formal writing., Spelling it as 'momm' or 'mome'.Confused with 'mom', which is American English., Used in formal contexts where 'mother' is preferred., Mispronounced as 'muhm' instead of 'mum'.
Usage notesUsed casually and affectionately. In formal settings, 'mother' is often preferred. 'Mom' is less appropriate in professional communication.Used primarily in British and Australian English. More casual than 'mother'. Not appropriate in formal writing or speech.

See it in real clips

Mom

Frequently asked questions: Mom vs Mum

What's the difference between Mom and Mum?

Mom: A female parent or mother. Mum: A word for mother.

Which is more formal: Mom and Mum?

Mom is the most formal of these.

Which is more advanced: Mom and Mum?

Mom is the highest level, at B1, on the CEFR scale.

Are Mom and Mum the same CEFR level?

Mom: B1, Mum: A1 on the CEFR scale.

What part of speech are Mom and Mum?

Mom: noun, Mum: noun.

Can you show an example of each?

Mom: Where's my mom? Mum: Mum is making dinner for the whole family.

Can I use Mom and Mum interchangeably?

Not always. Mom and Mum are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

Related comparisons