Dates and numbers
How to format dates, numbers, currency, punctuation and lists.
Dates
The standard format is DD MMM YYYY: day as a numeral, month as a 3-letter abbreviation, full 4-digit year.
| Format | Example | Use when |
|---|---|---|
| Standard | 14 Jan 2025 | Default for all UI: tables, lists, labels, messages |
| Long | Monday 14 January 2025 | Formal contexts, confirmations, when space allows |
| ISO numerical | 2025-01-14 | System or API use only, not agent-facing UI |
Do not use US date format: January 14, 2025 or 01/14/2025.
Date ranges
Use to. Avoid hyphens or dashes in running text.
Do
14 Jan to 28 Feb 2025
Don't
14 Jan - 28 Feb 2025
Relative time
When showing elapsed time or time remaining, use natural language units. Switch from smaller to larger units at the appropriate threshold.
Do
1 hour ago, 3 days ago, 2 months ago
Don't
60 minutes ago, 1 days ago
For remaining time: About 1 hour remaining, 2 minutes remaining
Seasons
Avoid references to seasons, they are hemisphere-dependent and ambiguous. Use months or quarters instead.
Do
April to June 2025
Don't
Autumn 2025
Numbers
-
Spell out numbers one to nine; use numerals for 10 and above.
-
If a number begins a sentence, spell it out regardless of size.
Do
Twelve accounts match this address.
Don't
12 accounts match this address.
-
If one number in a group requires a numeral, use numerals for all numbers in that group.
Do
The account has 1 direct debit and 12 payment records.
Don't
The account has one direct debit and 12 payment records.
-
Spell out fractions in running text.
Do
Two-thirds of accounts on this tariff
Don't
2/3 of accounts on this tariff
-
Always use numerals for percentages (use the % symbol, not the word), measurements, currency, and data values in tables.
-
Separate thousands with a comma: 1,200 not 1200.
-
Use a full stop for decimals: £12.50 not £12,50.
-
For large round numbers, spell out the word: 81 million not 81,000,000. Use abbreviations (K, M, B) only in charts or space-constrained table cells, with a space: 71 M records.
Currency
Use the appropriate symbol with no space before the amount.
- UK: £1,200.50
- AU: $1,200.50 (no AUD prefix unless disambiguation with another dollar currency is needed)
Punctuation reference
| Mark | Rule |
|---|---|
| Full stop | Not at the end of standalone labels, headings, or buttons. Use in body content and multi-sentence messages. |
| Oxford comma | Use in lists of three or more: Name, address, and date of birth |
| Colon | Use to introduce a list or simplify a complex sentence. Not at the end of a form field label. |
| Em dash (—) | Do not use in product content. Use a comma, colon, or full stop instead. |
| En dash (–) | For numerical ranges only when to cannot be used, e.g., in tight table cells: FY2024–25. No spaces around it. |
| Hyphen | For compound modifiers: up-to-date records, third-party supplier. No spaces. |
| Ellipsis (...) | Only for truncated content or loading states: Loading.... Not for effect or in button labels. |
| Ampersand (&) | Use and in content. & is acceptable in navigation labels only where space is severely constrained. |
| Exclamation mark | Avoid. Never in error messages, failure states, or alerts. |
| Semicolon | Avoid entirely. Use a full stop or comma instead. |
| Slash (/) | Do not use to combine words: avoid and/or, his/her. Choose one or restructure. |
| Emoji | Never use in product content. |
Lists
- Use bulleted lists for two or more concepts of equal weight.
- Use numbered lists for sequential steps.
- Lead into a list with an introductory phrase ending in a colon: You can choose:
- Use parallel construction, if items are actions, all should start with a verb; if nouns, all should be nouns.
- Capitalise the first letter of each list item.
- Do not use terminal punctuation in list items unless the item is a complete sentence. If one item needs a full stop, all items need one.