Personalised vs. Personalized: The Great Spelling Divide

When you look closely at the digital landscape, marketing copy, or product packaging, you might notice a subtle shift in spelling depending on where you are in the world. Is it personalised or personalized?

The short answer is simple: both are correct. The difference comes down to regional spelling preferences rather than a matter of right and wrong. Here is everything you need to know about why this split exists and how to choose the right spelling for your audience.

The Core Difference: Regional English

At its root, this is a classic clash between British English (UK/Commonwealth) and American English (US).

• Personalized (with a “z”): Standard in American and Canadian English. It follows the American convention of using the suffix -ize for verbs derived from Greek roots.
• Personalised (with an “s”): Standard in British, Australian, New Zealand, South African, and Irish English. It follows the British convention of preferring -ise suffixes.

Quick Regional Reference

| Region | Preferred Spelling | Example Style Guide |
| :— | :— | :— |
| United States | Personalized | Associated Press (AP), Chicago Manual of Style |
| United Kingdom | Personalised | Oxford style, BBC, The Guardian |
| Canada | Personalized (mostly) | The Canadian Press |
| Australia & New Zealand | Personalised | Style Manual for Authors, Editors and Printers (Australia) |

Why Does This Spelling Split Exist?

To understand why an “s” and a “z” are fighting over a single word, we have to look back at the history of English lexicography.

In the late 18th and early 19th centuries, American lexicographer Noah Webster sought to simplify American English spelling to distinguish it from British traditions. He favored phonetic spellings and standardized the -ize ending for many verbs (such as realize, recognize, and personalize).