Pledge vs Swear

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

Pledge

Formal Top 2,000 (common) C1 verb

Swear

Informal Top 2,000 (common) B2 verb

Most formal: Pledge

	Pledge	Swear
Pronunciation	🇬🇧 //plɛdʒ// 🇺🇸 //plɛdʒ// Hear Pledge	🇬🇧 /["/sweə(r)/","/sweəz/","/swɔː(r)/","/swɔːn/","/ˈsweərɪŋ/"]/ 🇺🇸 /["/swer/","/swerz/","/swɔːr/","/swɔːrn/","/ˈswerɪŋ/"]/ Hear Swear
Meaning	To make a serious promise or commitment.	To use rude or offensive words.
Example	She decided to pledge her support to the charity event.	I swear to tell the truth in my testimony.
Register	Formal	Informal
How common	Top 2,000 (common)	Top 2,000 (common)
CEFR level	C1	B2
Part of speech	verb	verb
Collocations	pledge allegiance, pledge support, pledge a donation	loudly, quietly, silently, hear somebody, at, solemnly, on oath, under oath, be prepared to, make somebody, by, on, to, be sworn into office, swear somebody to secrecy, swear somebody to silence, solemnly, on oath, under oath, be prepared to, make somebody, by, on, to, be sworn into office, swear somebody to secrecy, swear somebody to silence, solemnly, on oath, under oath, be prepared to, make somebody, by, on, to, be sworn into office, swear somebody to secrecy, swear somebody to silence, solemnly, on oath, under oath, be prepared to, make somebody, by, on, to, be sworn into office, swear somebody to secrecy, swear somebody to silence
Antonyms	renounce, disavow, withdraw	praise, compliment
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 'swear' with 'promise' — they have different meanings., Using it in formal writing where it's not acceptable., Using 'swear to' instead of 'swear at' when expressing anger.
Usage notes	Typically used in formal contexts, such as during ceremonies or official statements. Avoid in casual conversations.	Used in informal settings to express anger or frustration. Often considered inappropriate in formal contexts. Be cautious of the audience and setting before using.

Frequently asked questions: Pledge vs Swear

What's the difference between Pledge and Swear?

Pledge: To make a serious promise or commitment. Swear: To use rude or offensive words.

Which is more formal: Pledge and Swear?

Pledge is the most formal of these.

Are Pledge and Swear the same CEFR level?

Pledge: C1, Swear: B2 on the CEFR scale.

Can I use Pledge and Swear interchangeably?

Not always. Pledge and Swear 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.