What's the Character Limit for an Amazon Sponsored Brands Headline?

An Amazon Sponsored Brands headline is capped at 50 characters, including spaces, across the U.S. and most Amazon marketplaces. Japan is the one notable exception, where the limit drops to 35 characters.

Content Rules That Apply Alongside the Character Limit

A headline that fits within 50 characters can still get rejected if it breaks Amazon's creative acceptance rules. The main ones:

• Sentence case is required — only the first word of the headline is capitalized; the rest stays lowercase, regardless of how the brand normally styles its own name or slogans elsewhere.
• No unsubstantiated promotional language — phrases like "Best Price," "On Sale," or "#1" aren't allowed unless backed by a verifiable third-party source that Amazon can check during review.
• No competitor brand names — a headline can't reference another brand to draw a direct comparison, even an implied one.

Both the length limit and these content rules get checked during ad review, so a technically short, compliant-length headline isn't automatically a safe one if it trips one of these content restrictions.

Why Amazon Keeps the Limit This Tight

Sponsored Brands headlines run in a compact unit alongside a brand logo and a row of featured products, typically displayed above or within search results. There's limited horizontal space to work with on both desktop and especially mobile layouts, and Amazon's format is built around quick scanning rather than a paragraph of persuasive copy competing for attention next to organic listings.

Why Japan Gets a Shorter Limit

The 35-character cap for the Japan marketplace reflects how much more visual space double-byte Japanese characters occupy compared to single-byte Latin characters in the same ad unit. A shorter character allowance keeps the rendered headline width roughly consistent with other marketplaces rather than letting Japanese headlines run visually longer than English ones at the same character count.

What to Do With the Space You Have

Since promotional superlatives are restricted and the character count is short, the headline works best as a direct statement of what the brand or product category offers — the persuasion and proof points belong on the product detail page and in Sponsored Brands' supporting creative (logo, custom images, or video), not crammed into the headline itself.

How This Differs From Sponsored Products

The 50-character headline field is specific to Sponsored Brands (and the similarly structured Sponsored Display format) — it doesn't apply across every Amazon ad type. Sponsored Products ads don't have a separate custom headline at all; they display the product's existing listing title and main image pulled directly from the product detail page, so there's no headline length decision to make for that format. The headline limit only comes into play once an ad format includes a brand-level creative slot above or alongside the product listings, which is what makes Sponsored Brands distinct.

Bottom Line

Write Sponsored Brands headlines to 50 characters (35 for Japan), in sentence case, without competitor names or unverified superlatives — treat the headline as a label, not a pitch.

Source: Amazon Ads, Sponsored Brands creative acceptance policies and ad specifications (advertising.amazon.com).