As a general rule, United States (US) writers capitalize more than British (UK) writers. The United Nations uses UK style. Thus, in a heading, a UK writer would only capitalize the first letter of the first word, while the US writer would capitalize all words except conjunctions (e.g. and, or, but, nor, yet, so, for), articles (a, an, the), and prepositions (e.g. in, to). Proper nouns and other names that are usually capitalized remain capitalized in both styles, of course:
Background to the Rwandan project (UK)
Background to the Rwandan Project (US)
Test yourself.
Try your hand with these headlines from recent media headlines. Write them in UK style and then in US style (I’ve put everything in lower case).
1 sting sued by ex-police bandmates over royalties
2 korea’s tattoo artists are grabbing attention, at home and abroad
3 trump administration live updates: appeals court blocks deportations under alien enemies act
Answer key
1 Sting sued by ex-Police bandmates over royalties
1 Sting Sued by Ex-Police Bandmates Over Royalties
2 Korea’s tattoo artists are grabbing attention, at home and abroad
2 Korea’s Tattoo Artists are Grabbing Attention, at Home and Abroad
3 Trump administration live updates: Appeals court blocks deportations under Alien Enemies Act
3 Trump Administration Live Updates: Appeals Court Blocks Deportations Under Alien Enemies Act
Check with your style guide what the preferred style is, but above all, be consistent.
Here is the United Nations guideline: