What an outbound link is
An outbound link, sometimes called an external link, goes from a page on your site to a page on a different site. When you write that a figure comes from a government statistics page and link to it, that is an outbound link. It is the mirror image of a backlink: the same link is an outbound link for the site that places it and a backlink for the site that receives it.
Why link out at all
Some owners worry that sending visitors elsewhere is a mistake, as if each link lets a reader escape. In practice, links to good sources tend to serve the reader and, in turn, the site:
- Verification. Readers can check a claim and see that it is supported.
- Context. A link can point to background that would take too long to repeat.
- Credibility. Showing your sources signals that you did your homework. This fits with what helpful content looks like: it is clear about where information comes from.
- Fairness. Crediting the original source of data, an image or an idea is honest practice.
Whether outbound links affect rankings directly is not publicly known. Some believe they help search engines understand a page’s context, and others think the effect is small. Without clear evidence, the safest reason to link out is that it improves the page for people.
When to cite
Add a source whenever you:
- State a specific fact, figure, date or rule that a reader might want to verify.
- Quote or closely paraphrase someone else’s work.
- Rely on someone else’s research or data.
- Use an image, chart or text that is not yours and is licensed for reuse with attribution.
- Refer readers to official guidance, such as a regulator’s page.
For general knowledge that is widely understood, a citation is rarely necessary. Do not clutter a page with links that add nothing.
Choosing good sources
Prefer sources that are:
- Primary or authoritative: the original data, the official publication, the study itself, rather than a chain of articles repeating one another.
- Current: an old page may describe rules that have changed.
- Stable: established organizations are more likely to keep addresses working.
- Relevant: closely tied to the specific claim.
- Reasonably accessible: note it when the source is behind a login or paywall.
Avoid linking to pages you have not read. If a destination is unreliable, thin or hacked, a link from you suggests you vouch for it. Linking carelessly can also bring readers to a page with spam, one of the warning signs of hacked content on a third-party site.
Wording outbound links
Use descriptive text that tells readers where they are going, following the same principles as anchor text. “The agency’s published guidance on food labeling” is more helpful than “click here.” Name the source when it matters: “according to the national statistics office’s annual report.” Do not link entire sentences, and do not hide links in ways readers would not expect.
Attributes and outbound links
For editorial links to sources you trust, no attribute is usually needed. If a link is paid, affiliate or otherwise compensated, use the sponsored label. If you link to something and do not want to endorse it, nofollow is appropriate. These are explained under link attributes. Do not apply nofollow to everything out of fear; a page that cites sources openly is often better for it.
Opening in a new tab
Whether external links should open in a new tab is debated. Many accessibility guides suggest letting users decide, since opening a new tab unexpectedly can disorient people who use assistive technology. If you do choose it, it helps to signal that to readers, for example with a note in the link text. Consistency across the site matters more than the specific choice.
Keeping outbound links healthy
Links rot. Pages move, organizations restructure and addresses disappear. A page full of dead links looks neglected and frustrates visitors. To limit this:
- Check outbound links during routine reviews, using a crawler or periodic spot checks, as part of fixing broken links and error pages.
- When a source has moved, update the link. When it is gone, find another source or remove the claim if it cannot be supported.
- For critical citations, note the date you accessed the source in the text, so readers know when the claim was last verified.
- Be cautious about linking to short-lived pages, such as promotions or temporary news items.
How many is too many
There is no fixed number. Link where it is useful and stop. A long reference article may reasonably cite many sources, while a short product page may need none. If links crowd the text so heavily that reading becomes difficult, trim them to the most helpful ones.
Linking and trust
Be careful about the company you keep. Linking regularly to low-quality or deceptive sites can reflect poorly on your own. Also avoid arrangements where you place outbound links in exchange for something without disclosure, which relates to link schemes. Honest citations are the foundation of a credible page, and each one is a small promise to the reader that you checked.