Mastering English Months: Starting Your Language Journey with January
In Spanish grammar, months, days of the week, and seasons remain lowercase unless they open a sentence: "Hoy es 24 de enero." English follows a strict rule: all months of the year in English are proper nouns. Writing "january" with a lowercase letter is a grammatical error across all standard academic and professional style guides.
Shortened forms also follow strict punctuation conventions. The standard abbreviation for January is Jan., which takes a period in standard American editorial styles (Chicago, AP, and MLA). In digital database design or ISO calendar formats, you may see the unpunctuated three-letter string "JAN", but human-written prose requires the trailing period when abbreviated.
Seasonal labels operate under the opposite rule. While January must be capitalized, the season it occupies, winter, remains lowercase unless it begins a sentence or forms part of a formal title like the "Winter Olympics 2026."