Pledge vs Promise

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

Pledge

Formal Top 2,000 (common) C1 verb

Promise

Top 1,000 (very common) A2 verb

Most formal: Pledge Most common: Promise

	Pledge	Promise
Pronunciation	🇬🇧 //plɛdʒ// 🇺🇸 //plɛdʒ//	🇬🇧 /["/ˈprɒmɪs/","/ˈprɒmɪsɪz/","/ˈprɒmɪst/","/ˈprɒmɪsɪŋ/"]/ 🇺🇸 /["/ˈprɑːmɪs/","/ˈprɑːmɪsɪz/","/ˈprɑːmɪst/","/ˈprɑːmɪsɪŋ/"]/
Meaning	To make a serious promise or commitment.	A commitment to do something or not do something.
Example	She decided to pledge her support to the charity event.	I promise to help you with your homework.
Register	Formal	Neutral
How common	Top 2,000 (common)	Top 1,000 (very common)
CEFR level	C1	A2
Part of speech	verb	verb
Collocations	pledge allegiance, pledge support, pledge a donation	faithfully, solemnly, initially, can, cannot, seem to, to, as promised, I can’t promise anything
Antonyms	renounce, disavow, withdraw	lie, break, betray
Common mistakes	Confused with 'pledged' vs 'pledge' as different tenses., Omitting the object after the verb., Using 'pledge' when referring to a general promise instead of a formal commitment.	Confusing 'promise' with 'vow' or 'pledge' in terms of strength., Using 'promise' without an object (e.g., 'I promise' should specify what)., Misusing in the past tense (e.g., 'I promised' without a follow-up).
Usage notes	Typically used in formal contexts, such as during ceremonies or official statements. Avoid in casual conversations.	Use 'promise' when you want to express a vow or assurance. Common in both spoken and written contexts, but avoid in formal legal documents.

See it in real clips

House Of Dragons › S1 E1

I pledge fealty to them

House Of Cards › S1 E1

Can we make that pledge?

House Of Dragons › S1 E1

I pledge fealty to them

House Of Cards › S1 E1

Can we make that pledge?

Pledge

And one system shows promise.

and I always try to keep my promise.

And one system shows promise.

and I always try to keep my promise.

Promise

Frequently asked questions: Pledge vs Promise

What's the difference between Pledge and Promise?

Pledge: To make a serious promise or commitment. Promise: A commitment to do something or not do something.

Which is more formal: Pledge and Promise?

Pledge is the most formal of these.

Which is more common: Pledge and Promise?

Promise is the most common in everyday English.

Which is more advanced: Pledge and Promise?

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

Are Pledge and Promise the same CEFR level?

Pledge: C1, Promise: A2 on the CEFR scale.

What part of speech are Pledge and Promise?

Pledge: verb, Promise: verb.

Can you show an example of each?

Pledge: She decided to pledge her support to the charity event. Promise: I promise to help you with your homework.

Can I use Pledge and Promise interchangeably?

Not always. Pledge and Promise 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.