Nofollow, Sponsored and UGC Links: Choose the Right rel Attribute

When your site links to another page, you can say something about that link by adding a rel attribute to it. Google recognizes three values for this: nofollow, sponsored and ugc. Picking the wrong one is not a disaster, but leaving paid links unmarked can put you on the wrong side of Google's link spam policy, and marking everything nofollow out of habit throws away a useful signal for the pages you do trust.

This guide is for site owners, bloggers, publishers and developers who link out: from articles, from advertising slots, from affiliate and sponsored posts, and from comment sections and forums. You will learn what each value means, which one to use in each situation, how to write the HTML, how to automate it in a CMS, and how to audit what you already have. It also explains the limits. These attributes tell Google how you relate to a link. They do not promise a ranking change for anyone, and they do not control indexing of your own pages.

Before you begin

You need to know where your site links out. Make a list of the places that publish links which you did not simply choose as editorial recommendations: ad units, sponsored posts, affiliate programs, press releases, partner pages, widgets, comments, forum posts, profile pages and reviews left by visitors. You also need edit access to the templates or plugins behind those areas, since the attribute is usually added by the system and not by hand.

Take a backup of the templates you edit. Allow an hour for a small site. The risk is low, because adding a rel value to an outbound link does not remove the link for visitors.

What each value means

Google's documentation on qualifying outbound links describes the three values this way.

sponsored is for advertisements or paid placements, commonly called paid links. Google prefers it over nofollow for these links, though it says nofollow is still an acceptable way to flag them.

ugc is for user-generated content, such as comments and forum posts.

nofollow is for cases where neither of the other two applies and you do not want Google to associate your site with the linked page or crawl it from your site.

An ordinary editorial link needs no rel attribute at all. Google fetches and parses it normally.

Google says links marked with these attributes will generally not be followed. It also reminds you that the linked pages may still be found through other means, such as sitemaps or links from other sites. Use these attributes on <a> elements that Google can crawl, since that is where they apply.

Step-by-step instructions

Step 1: Sort your outbound links into groups

Go through your list and sort each type of outbound link into one of four groups:

Editorial links you chose freely because they help readers. No attribute needed.
Paid or sponsored links: anything you were paid, given goods or services, or otherwise rewarded for, including links in advertorials, sponsored posts and ads.
User-generated links: links added by visitors in comments, forums, profiles and reviews.
Other links you do not want to vouch for: for example, a link to a site you are discussing as a bad example.

Google's link spam policy describes paid links as exchanging money, goods or services for links, or sending a product in exchange for writing about it with a link. Treat affiliate and gifted-product links as belonging in group 2 if a reward depends on them.

What success looks like: each type of link on your site is in exactly one group.

Step 2: Choose the value for each group

Match the group to the value:

Group 1: no rel attribute.
Group 2: rel="sponsored". Google's spam policy says paid links are acceptable when the <a> tag has rel="nofollow" or rel="sponsored", and the link documentation says it prefers sponsored for these.
Group 3: rel="ugc".
Group 4: rel="nofollow".

You can use more than one value on one link, separated by spaces or commas. For example, rel="ugc nofollow" is valid, and Google's documentation lists both the space and the comma forms. Combining is useful when you want to be explicit, or when older systems only understand nofollow.

What success looks like: a written rule, one line per group, that your team can follow.

Step 3: Write the HTML correctly

Here is how the markup looks, using example.com URLs:

<!-- Editorial link: no rel needed -->
<a href="https://www.example.com/guide">Planting guide</a>

<!-- Paid placement or advertisement -->
<a href="https://www.example.com/offer" rel="sponsored">Garden tools offer</a>

<!-- Link left by a visitor in a comment -->
<a href="https://www.example.com/profile" rel="ugc">my site</a>

<!-- A link you do not want to vouch for -->
<a href="https://www.example.com/example-of-bad-practice" rel="nofollow">this example</a>

<!-- Combined values -->
<a href="https://www.example.com/post" rel="ugc nofollow">a post</a>

Add the attribute to the <a> element itself.

What success looks like: viewing the page source shows the right rel value on each outbound link in the group.

Step 4: Automate it in your CMS or templates

Hand-editing every link does not scale. Google's SEO starter guide recommends configuring your CMS so that user-posted links get nofollow or a similar annotation automatically. Most comment and forum systems have a setting for this, and many allow ugc specifically. Check the setting, then post a test comment with a link and inspect the HTML.

For advertising and affiliate links, put the attribute into the template or widget that creates the link, so that new links are marked from day one. If an affiliate network gives you link code, add rel="sponsored" to it unless the network already does. If a plugin changes your links, check what the rendered page contains and not only the plugin's description.

What success looks like: a test comment link and a test affiliate link both carry the right value in the rendered HTML.

Step 5: Decide whether to reward trusted contributors

Google says that if you want to recognize and reward trustworthy contributors, you might remove the ugc attribute for members who consistently contribute high-quality content over time. Whether to do that is a business choice. If you do, keep it tied to a clear rule, such as an account age and a number of approved posts, and review it so spammers cannot earn trusted status cheaply.

What success looks like: either all user links are marked, or a documented trust rule decides when the attribute is removed.

Step 6: Do not use nofollow to manage your own site

For links within your own site, Google's guidance is to use a robots.txt disallow rule if you do not want a page fetched. To keep a page out of the index, allow crawling and use a noindex rule. Using nofollow on internal links to hide pages is an unreliable control, because the page can still be found through other links or a sitemap. If the aim is to limit crawling of low-value URLs, see Robots.txt Blocking Google or Bing for how those rules behave, and Fix Duplicate URLs and Incorrect Canonical Tags for consolidating duplicates.

What success looks like: internal links carry no nofollow, and any crawl control is done with the right tool.

Step 7: Audit what you have

Crawl the site and export every outbound link with its rel value. Filter for domains you have commercial relationships with, and for links inside comments and forum areas. Look for sponsored links with no attribute, user links with no attribute, and editorial links that are nofollow for no reason. The robots meta tag also supports nofollow. That is a separate, page-level setting, so check pages for it too, using Choose the Right Meta Robots Directive.

What success looks like: a list of exceptions with an owner and a fix date.

Step 8: Keep editorial links clean and honest

Link to sources you trust, because Google's starter guide says to link to trustworthy resources and to annotate links you do not trust. Describe the destination in the anchor text so readers know where they will land. Do not trade links, run link exchanges beyond what readers would find natural, or require partners to link without letting them qualify the link, as the spam policy lists those. If someone asks you to remove a sponsored attribute from a paid link, decline.

What success looks like: every outbound link is either an honest editorial choice or properly qualified.

Final verification checklist

Editorial links have no rel attribute unless you have a reason.
Paid, advertising and affiliate links carry sponsored (or nofollow).
User-generated links carry ugc (alone or with nofollow).
Links you do not want to vouch for carry nofollow.
A test comment and a test ad link show the right attribute in the rendered HTML.
No internal links use nofollow to hide pages.
Pages you want indexed do not have an unintended nofollow robots meta tag.
A crawl export shows no unmarked paid or user links.

Common mistakes to avoid

Leaving paid links unmarked. Qualify them with sponsored or nofollow.
Using nofollow on everything. Editorial links to good sources need no attribute.
Blocking your own pages with nofollow. Use robots.txt for crawling and noindex for indexing.
Putting the attribute in the wrong place. It belongs on each <a> element, not on a wrapper such as a <div>.
Believing it hides pages. Linked pages can still be found by sitemaps and other sites.
Forgetting widgets and embeds. Third-party widgets may inject unmarked links.
Trusting plugin descriptions. Check the rendered HTML.
Mixing page-level and link-level controls. A robots meta nofollow is a separate setting from a link's rel value, so check both.

Frequently asked questions

Is `ugc` better than `nofollow` for comments?

ugc tells Google more precisely what the link is. Google also accepts nofollow and lets you combine them, such as ugc nofollow.

Do I need `sponsored` on affiliate links?

If you earn from the link, treat it as a paid placement. Google's policy says paid links are fine when qualified with sponsored or nofollow.

Does nofollow stop Google crawling the target?

Not reliably. Google says the linked page can still be found by other means, such as sitemaps.

Can I use more than one value?

Yes. Separate values with spaces or commas, for example ugc nofollow.

Do these attributes affect my own rankings?

Google does not promise any ranking effect. Their main job is to describe the link honestly and keep your site in line with its link spam policy.

Official references

Next step: See how Crawvix checks a website and capture a baseline once scanning opens. This guide provides technical information, not a guarantee of rankings, traffic or index inclusion.