Do you have to disclose if you have an affiliate link?
If your affiliate content falls under the UK advertising rules, then yes in practice: the Advertising Standards Authority's CAP Code requires marketing communications to be obviously identifiable, and its published guidance says that where a commercial relationship is not clear from context, some form of additional disclosure is likely to be required. The exact duty depends on where you and your audience are, so verify the rules for your own jurisdiction.
A straight answer exists for UK-relevant content, and it comes from the Advertising Standards Authority, the body that administers the CAP Code there. Affiliate marketing is, in the ASA's words, performance-based marketing where an affiliate is rewarded by a business for each new customer attracted, usually with a pre-agreed commission on each sale. Because those references are directly connected with the supply of goods and services, the CAP Code applies to them. Both the business running the scheme and the affiliate are responsible under the Code, even if the affiliate wrote the content alone.
[1]What the rules actually say
Rule 2.1 of the CAP Code requires that marketing communications are obviously identifiable as such, and rule 2.3 requires that they make clear their commercial intent where that is not apparent from the context. The ASA accepts that some formats — banner ads, branded emails, cashback sites — are obviously identifiable by their nature. But in blogs, news sites, voucher sites and social media, the commercial relationship may not be clear, particularly where the author is primarily a creator of non-commercial content. In those cases, the ASA says some form of additional disclosure is likely to be required so the affiliate content is obviously identifiable as a marketing communication.
[1]The guidance is also specific about what does not work. A disclaimer at the bottom of a post is unlikely to be sufficient, because the links would not be obviously identifiable at the moment the reader encounters them. A vague disclaimer saying the author may receive a commission is unlikely to be acceptable either — in one ruling against MailOnline, the ASA judged the phrase may earn an affiliate commission ambiguous and confusing, because it suggested payment might not happen when it normally would. The ASA has also found standalone labels like a lone asterisk-affiliate tag on an Instagram Story insufficient, partly because the term affiliate itself is not widely understood by consumers.
[1]An everyday comparison
Picture two small comparison sites, purely as an illustration. The first quietly inserts paid links into its buying guides and mentions nothing. The second marks the relevant content clearly — an identifier such as Ad before the affiliated parts, or a clear statement up front explaining that asterisked links mean the author receives a share of sales. Under the ASA's approach, the second site is doing what the Code expects; the first risks the kind of breach the ASA has already ruled on, such as a fashion blog with unlabelled affiliate links next to featured products. Separately from any regulator, affiliate networks and merchants commonly set their own programme terms that partners must meet.
[1]Practical steps
- Work out which rules apply to you. The CAP Code is the UK framework; if your business or audience sits elsewhere, check your own jurisdiction's consumer and advertising rules.
- Make the commercial nature clear before the reader engages with the affiliate content, not after — the ASA treats bottom-of-page disclaimers as unlikely to be sufficient.
- Avoid ambiguous wording. Say plainly that you receive a share of sales through the links, rather than that you may receive a commission.
- Read the terms of each affiliate programme you join; merchants and networks often impose their own promotional rules on top of what the law requires.
- If you are unsure of your legal obligations, ask a qualified adviser in your jurisdiction.
For context on where this site is coming from: 37X Ventures is operated by 37x Limited, a Guernsey company, and its published working method treats programme compliance and transparency as operating requirements. Its founder's background is in affiliate-funded businesses, including DiscountVouchers.co.uk, which operated on an affiliate-funded model before its sale in 2016. That is operating history, not legal advice — but it explains why the question of disclosure is taken seriously here.
[3]Sources and dates
- https://www.asa.org.uk/advice-online/affiliate-marketing.html · accessed 2026-10-18
- https://37xventures.com/ · accessed 2026-10-18
- https://37xventures.com/ · accessed 2026-10-18