Backup vs Reserve

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

Backup

Top 1,000 (very common) C1 noun

Reserve

Top 1,000 (very common) B2 noun

	Backup	Reserve
Pronunciation	🇬🇧 /["/ˈbækʌp/"]/ 🇺🇸 /["/ˈbækʌp/"]/	🇬🇧 /["/rɪˈzɜːv/"]/ 🇺🇸 /["/rɪˈzɜːrv/"]/
Meaning	A copy of data to keep safe.	To keep something for future use.
Example	The police had backup from the army.	I would like to make a reserve for dinner tonight.
Register	Neutral	Neutral
How common	Top 1,000 (very common)	Top 1,000 (very common)
CEFR level	C1	B2
Part of speech	noun	noun
Collocations	data backup, create a backup, backup plan, full backup	great, huge, large, have, hold something in, keep something in, be available, dwindle, fall, assets, currency, funds, in reserve, reserve of, national, bird, forest, create, establish, national, bird, forest, create, establish, deep, natural, with reserve, without reserve, deep, natural, with reserve, without reserve, play in, side, team, goalkeeper, play in, side, team, goalkeeper, air-force, army, marine, army, force, police
Antonyms	delete, erase, lose	release, give up, share
Common mistakes	Using 'backup' as a verb incorrectly; it's often used as a noun., Confusing 'backup' with 'backup up' which implies physical support rather than data., Not distinguishing between the types of backups (full, incremental).	Confused with 'preserve' which means to keep in good condition., Using 'reserve' incorrectly as a noun instead of a verb., Omitting the object when saying 'reserve' (e.g., should say 'reserve a table').
Usage notes	Use in tech contexts when discussing data safety. Formal in business settings, neutral in casual conversations. Avoid in informal spoken language.	Use 'reserve' when talking about booking a place or holding items. It's common in formal contexts like restaurants or hotels. Avoid using it in casual conversation when discussing very personal or informal topics.

See it in real clips

Backup. Send backup.

Backup

Band Of Brothers › S1 E1

I've still got my chute, my reserve chute, my Mae West, my M-1.

Breaking Bad › S1 E1

Well, I met my reserve and there's still two minutes.

Band Of Brothers › S1 E1

I've still got my chute, my reserve chute, my Mae West, my M-1.

Breaking Bad › S1 E1

Well, I met my reserve and there's still two minutes.

Reserve

Frequently asked questions: Backup vs Reserve

What's the difference between Backup and Reserve?

Backup: A copy of data to keep safe. Reserve: To keep something for future use.

Which is more advanced: Backup and Reserve?

Backup is the highest level, at C1, on the CEFR scale.

Are Backup and Reserve the same CEFR level?

Backup: C1, Reserve: B2 on the CEFR scale.

What part of speech are Backup and Reserve?

Backup: noun, Reserve: noun.

Can you show an example of each?

Backup: The police had backup from the army. Reserve: I would like to make a reserve for dinner tonight.

Can I use Backup and Reserve interchangeably?

Not always. Backup and Reserve 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.