B vs. Bn for Billion
There is no single universal abbreviation for “billion.” Government of Canada guidance documents “B” but warns against it in formal writing, while the University of Reading uses “bn” in its money style and Microsoft product displays use “B” for compact numbers. The governing house style should decide.
“B” and “bn” both occur, but they are style-dependent; spell out “billion” when clarity or formal prose matters and no house style specifies an abbreviation.
Key details
Important caveats
Usage Boundary
Use the abbreviation specified by the publication, product, or financial style; otherwise writing “billion” in full is usually clearer.
Further guidance
B Form
“B” is used in some compact or journalistic/display contexts, but at least one government writing reference advises against it in formal prose.
Bn Form
“bn” is an explicit house-style abbreviation for billion in some institutional money formatting.
Practical Application
Follow the house style of the publication, product, or financial context. Use “B” where that compact display convention is established, “bn” where the editorial style specifies it, and spell out “billion” when clarity or formal prose matters more than compression.
Reader Check
Would a reader know which abbreviation system the document is using without a legend or prior convention? If not, “billion” in full is safer.
Worked Example
Dashboard under a “B” convention: “Revenue: $2.4B.” Formal sentence without a defined abbreviation style: “Revenue reached $2.4 billion.”
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- billion, B (billion) — Writing Tips Plus (opens in a new tab)Government of Canada Language Portal · Use and formality boundary for B as an abbreviation for billion
- University of Reading house style — abbreviations for money (opens in a new tab)University of Reading · House-style use of m, bn, and tn for money figures
- Configure display column properties — large-number abbreviations (opens in a new tab)Microsoft Learn · Product-interface examples using B and T for compact large-number display