Short answer
For a UK job application, a CV and a resume are the same document under two names. Use "CV", not "resume", and you're already halfway there.
Where the two words come from
"Resume" is American. "CV", short for curriculum vitae, is what the UK, Ireland and most of the Commonwealth call the same document. Neither word describes a fixed format; they describe whichever one-to-two-page summary of your work a local employer expects to see.
The genuine confusion is academic CVs, a separate document used in universities and research that lists every publication, grant and post someone has held, often running to ten pages or more. That is not what a UK employer means when they ask for your CV, and it is not what this page is about.
What actually changes
Length, mostly. A US resume is expected to fit one page, rewritten for each application, keeping only what is relevant to that specific role. A UK CV usually runs to two pages and keeps a fuller employment history, though the strongest ones still cut anything that does not earn its place.
Sections carry over almost exactly: contact details, a short personal statement, work experience in reverse order, education, and skills. Neither document includes references any more; both just say they are available on request, or leave the line out entirely.
The one mistake that actually costs interviews
A photo, date of birth, marital status or nationality on the CV. That convention is common in parts of continental Europe, not the UK. Most UK employers read it as a sign the applicant has not looked at a British CV before, and NHS and public sector application forms will actively ask you to leave it out, since it invites exactly the kind of bias equality law is meant to prevent.
If a template calls the photo field optional, treat it as a trap, not a feature.
Which word to actually use
Applying to a UK employer, including a UK office of a US company: say CV, on the document and in conversation. Applying to a US employer, or a role that specifically asks for a resume: trim to one page and call it that. The document underneath barely changes; the label and the length are what the reader is actually checking for.
Questions
Is a CV the same as a resume?▾
For a UK job application, yes, near enough. "CV" is just the word UK employers use for the document Americans call a resume. The confusion comes from academic CVs, which are a different, much longer document listing every publication and post someone has ever held. A job-application CV is not that.
What's the actual difference between a CV and a resume?▾
Mostly length and expectation. A US resume is trimmed to one page and rewritten per role, cutting anything not relevant to that specific job. A UK CV usually runs to two pages and keeps a fuller work history, though the good ones still cut anything that does not support the application.
Should I put a photo and date of birth on a UK CV?▾
No. That convention exists in parts of continental Europe, not the UK. Most UK employers, and every NHS or public sector application, will read a photo or date of birth as a sign the applicant hasn't looked at a British CV before. Leave both off.