Link building: strategy and Google’s rules

What is link building in SEO?

Link building, called “netlinking” in France, means acquiring inbound links from third-party sites. Each link obtained is called a backlink. Link building is the process, the backlink is its result. Our page defining a backlink details what makes a single link good.

Organic search rests on three pillars: technical, content and popularity. Technical work makes the site crawlable, content answers an intent, popularity shows that other sites recommend it. Link building works on the third. It never makes up for a weakness in the first two, as our SEO guide points out.

How much do links weigh in Google rankings in 2026?

Google confirms that it uses links. Its guide to ranking systems (updated on December 10, 2025) describes systems that analyse how pages link to one another. PageRank is one of them: present since the search engine launched, it has been heavily modified since. How this algorithm works is explained in our article on Google’s PageRank.

Google does, however, play down their weight. In April 2024, Gary Illyes said Google needed “very few links” to rank pages, according to Search Engine Journal. A recommendation based on link volume alone no longer holds. The relevance of the page carrying the link counts more than their number.

For AI answer engines, the brand’s reputation outside your site therefore matters too. This neighbouring workstream is covered on our page about GEO optimization.

What are the ways to get links?

The levers fall into four families. Their cost and their exposure to Google’s policies vary widely.

Family	Examples	Cost and lead time	Exposure to Google policies
Earned links	Press relations, original studies, reference content	High, long, uncertain	None
Requested links	Unlinked mentions, dead links to replace, suppliers, partners	Low, short to medium	None
Built links	Guest posts, directories, forums, profiles	Low to medium, short	Moderate if links are optimised at scale
Bought links	Sponsored article, link on an existing page, link rental	High, short	High if the link is not qualified

Unlinked mentions are often the most profitable source. A search for your brand, excluding your own domain, lists the pages that already mention you. All that is left is to ask for the link to be added.

Old pages that still receive links deserve the same attention. If they return a 404 error, a 301 redirect to the equivalent page recovers those links.

What Google prohibits, and what changes in France

Google’s spam policies (updated on August 28, 2026) define “link spam” as creating links to or from a site primarily to manipulate rankings. Targeted practices include:

• buying or selling links, including in exchange for a free product;
• excessive link exchanges;
• automatically generated links;
• low-quality directories.

Advertising is still allowed. A paid link complies if it carries rel="sponsored" or rel="nofollow". The Qualify your outbound links page explains how to use these attributes, as well as rel="ugc" for user-generated content.

A sponsored article published on a media site is also covered by the “site reputation abuse” policy. On November 19, 2024, Google clarified that the host’s editorial oversight does not exempt third-party content published to benefit from the site’s authority.

The rules changed at the end of August 2026. According to the same spam policies page, the pages concerned no longer receive a manual action when they are shown in the European Economic Area (EEA). Three caveats apply:

• the practice is still described as abuse;
• in the EEA, Google may treat these pages as separate from the main domain: they then lose the support of the host site’s authority;
• outside the EEA, a manual action is still possible.

How do you build a link building strategy?

A link building strategy is prepared before the first link. Here is the order we recommend.

1. Check that there is no manual action in Search Console and archive the links export. An unresolved manual action comes before everything else.
2. Audit the link profile and compare it with at least three competitors. The method is detailed in our backlink audit.
3. Choose the target pages and anchors before any purchase. Aim for strategic pages, very rarely the home page, never a URL that redirects.
4. Prepare internal distribution: a page that receives links must pass their value on through internal linking.
5. Qualify each site: legal notice, indexed host page, link in the body text, closely related topic, few other outbound links.
6. Spread acquisition over time. A spike in links followed by a drop is a profile often associated with unnatural links.
7. Track each link at D+7, D+30, D+90 and D+180: presence, attribute, indexing of the host page.

How do you measure the effect of a link campaign?

The first criterion is whether the page carrying the link is indexed. A page that is not indexed passes nothing on. The Search Console Links report shows only a sample: export it every month to spot links that appear and then disappear.

Majestic (Trust Flow), Ahrefs (Domain Rating), Moz (Domain Authority), Babbar or Haloscan are used to sort a list of sites. None of them reproduces Google’s calculation. A third-party score therefore justifies neither a purchase nor a disavow.

The disavow file still exists. On March 6, 2026, John Mueller pointed out that most sites do not need it, according to Search Engine Roundtable. It is mainly justified after a manual action for unnatural links.

Finally, judge the effect on the rankings of the target pages, query by query, over several months. No serious provider guarantees a position: a bought link can be removed or neutralised without notice.