Link Building: The Complete Guide
Link building is getting other websites to link to yours. How it works, which strategies still earn rankings, what it costs and how to start.
Link building is the work of getting other websites to link to yours. Each of those links acts as a vote of confidence, and search engines use them to decide which pages deserve to rank.
It's one of the oldest parts of SEO and still one of the hardest to fake. Content is easy to publish and technical fixes are within anyone's reach, but a link from a real, relevant site has to be earned, asked for or paid for, which is exactly why it still carries weight.
This guide covers the whole picture: what a link is worth, how the process works, which strategies are worth your time, how many links you need, what it costs, and where links fit now that AI answers sit on top of the results.
What is link building?
A link from another site to yours is called a backlink. If the idea is new to you, start with what backlinks are and how they pass authority, then come back.
Link building is the deliberate version of collecting them. Instead of waiting for people to stumble across your site and cite it, you create reasons for them to link and then put those reasons in front of the right people.
In practice that covers a wide range of work:
- Creating content or data that people want to reference
- Finding relevant sites and pitching them an article, a quote or a resource
- Getting coverage in the press through digital PR
- Reclaiming mentions of your brand that don't link yet
- Paying a service or agency to do the outreach for you
The goal is the same in every case: more relevant, trusted sites pointing at the pages you want to rank.
Why links still matter for SEO
Google was built on links. Its original PageRank system treated a link from one page to another as a signal of importance, and Google's own documentation says PageRank has evolved a lot since then but "continues to be part of our core ranking systems".
Links aren't the only signal and they can't rescue a weak page. But when two pages are similarly useful and similarly well optimised, the one with more relevant, trusted links usually wins. That's especially true for competitive commercial keywords, where every page on page one already has good content.
The concept of authority flowing through links has a nickname in the industry, link juice, and it explains why one link from the right page can matter more than dozens from the wrong ones.
Links also shape AI search. AI Overviews and chatbots lean on pages that already rank well and on brands that are widely cited, so the same work that earns rankings tends to earn citations. There's more on that below.
How link building works: the loop
Every successful campaign, whatever the tactic, runs the same loop. You need something worth linking to, a list of sites that might link, a pitch that gives them a reason to, and a live placement at the end. The rankings and traffic that follow make the next round easier.
- Asset. A page that deserves a link: original data, a genuinely useful guide, a tool, a product worth reviewing or an expert who can be quoted
- Prospect. A list of sites that cover your topic and plausibly link out to pages like yours, found with link building tools and search operators
- Pitch. A short, personal email that explains what's in it for them, which is where outreach email templates help
- Placement. The link goes live, ideally in the body of a relevant article with sensible anchor text
- Rankings. The target page climbs, picks up traffic and earns some links on its own
What makes a link worth building?
Not all links are equal, and the industry wastes a lot of money pretending they are. These are the signals that separate a link that moves rankings from one that does nothing.
| Signal | What to look for | Why it matters | Read more |
|---|---|---|---|
| Unique site | A domain that hasn't linked to you before | New referring domains count for more than repeat links | Referring domains |
| Relevance | The site and the article cover your topic | Relevance is what makes a link look editorial | What are backlinks |
| Real traffic | The site ranks for keywords and gets visitors | Traffic shows Google already trusts the site | Domain metrics |
| Link attribute | No nofollow or sponsored on editorial links |
Followed links are the ones that usually pass ranking credit | Dofollow vs nofollow |
| Authority | A reasonable score relative to your niche | Third-party scores like DR and DA are rough guides, not targets | DR vs DA |
| Placement | In the main body, near related text | Google's spam policies name widely distributed footer and template links | Link juice |
| Anchor text | Natural, varied, mostly branded | Keyword-stuffed anchors look manipulated | Anchor text |
If you only check one thing, check traffic. A site with a high authority score and no organic visitors is usually a site that exists to sell links.
Link building strategies that work
There are dozens of named tactics, but most fall into a handful of families. The link building strategies hub compares every one of them in detail; this is the summary.
| Strategy | How it works | Cost | Control over the link | Risk |
|---|---|---|---|---|
| Guest posting | Write an article for another site with a link back | Medium | High | Medium, if done at scale on weak sites |
| Blogger outreach | Pitch relevant bloggers to feature or mention you | Medium | Medium | Low to medium |
| Niche edits | Get a link added to an existing article | Medium | High | Medium |
| Digital PR | Pitch stories and data to journalists | High | Low | Low |
| Broken link building | Offer your page as a replacement for a dead link | Low | Medium | Low |
| HARO and journalist requests | Answer reporters looking for expert quotes | Low | Low | Low |
| Link reclamation | Turn unlinked brand mentions into links | Low | Medium | Low |
| Resource pages | Get listed on curated lists of useful links | Low | Medium | Low |
| Directory links | Submit to relevant, curated directories | Low | High | Low on good directories, high on spammy ones |
| PBNs | Links from networks built only to sell links | Low to medium | High | High |
Cost and risk here are relative, and they swing a lot depending on who does the work. As a rule of thumb, the tactics that give you the most control over the link (where it goes, what the anchor says) are also the ones that carry the most risk if they're done carelessly.
New sites should also cover the basics first. Foundational links such as business profiles and relevant directories won't move a competitive keyword on their own, but they make a profile look like a real business.
White hat, grey hat and black hat
Google's spam policies define link spam as creating links "primarily for the purpose of manipulating search rankings". Buying or selling links that pass ranking credit, excessive link exchanges, automated link building and low-quality directory links are all named.
That gives you a spectrum rather than a clean line:
- White hat links are earned or requested on merit: PR coverage, editorial mentions, genuine guest contributions
- Grey hat covers the large middle of the industry, such as paid outreach services and sponsored placements where the commercial side isn't always obvious
- Black hat means PBNs, link farms, hacked links and automated spam
The white hat vs black hat guide places every tactic on that spectrum, and the page on link schemes Google penalises covers Penguin, SpamBrain and the updates in between. The short version is that Google now mostly neutralises spammy links rather than penalising the site, so bad links are usually wasted money. Deliberate, large-scale manipulation can still earn a manual action.
How many links do you need, and how fast?
There's no universal number. The honest answer depends on who you're competing with, and the best way to find it is to compare your referring domains with the pages that already rank. The guide to how many backlinks you need walks through that gap method step by step.
Pace matters less than people think. A steady, consistent stream of relevant links looks like a site that's growing, while a sudden spike of low-quality links looks like a campaign. Google has never published a "safe" number per month, so anyone quoting one is offering a rule of thumb at best.
How to get your first backlinks
If you're starting from zero, work in this order:
- Fix your internal linking so the authority you already have reaches your important pages
- Claim the easy, legitimate links: business profiles, partner and supplier pages, relevant directories, and the free backlinks that are genuinely worth having
- Find unlinked mentions of your brand and ask for the link
- Build one asset worth citing, then promote it with outreach
- Add a scalable tactic such as guest posting or digital PR once you know what converts
The full walkthrough, including how to choose between earning, asking and paying, is in how to get backlinks.
Doing it yourself vs outsourcing
Link building is labour-intensive. Prospecting, pitching, writing and follow-up all take time, and response rates on cold outreach are low. That's why most businesses eventually pay someone to do at least part of it.
| Route | Best for | Main trade-off | Read more |
|---|---|---|---|
| In-house | Brands with time, writers and patience | Slow to start, cheap per link once it's running | Outsourcing link building |
| Freelancer | Small budgets, single niche | Quality varies wildly | Outsourcing link building |
| Agency or managed service | Teams that want results without the admin | Less control over which sites you get | Best link building services |
| Marketplace | Buyers who want to pick each site | You do the vetting | Link building marketplaces |
| White label | SEO agencies reselling to clients | Margin and quality depend on the provider | White label link building |
Before you spend anything, read how much link building costs so you know what a fair price looks like, and the guide to buying backlinks safely so you know what Google's policies say about paid placements. When you're ready to compare providers, the reviews and comparisons hub covers the main services against a published method.
Link building by industry
The tactics are the same everywhere, but the mix changes by niche. A dentist needs local citations and community links. A SaaS company needs comparison and integration mentions. A casino site needs publishers that will accept gambling content at all.
The industry guides cover the differences, including local businesses, SaaS, ecommerce and law firms.
Links and AI search
AI search hasn't replaced links, it has added a second audience for them. The systems behind AI Overviews and chatbots draw on pages that already rank well and on sources that are widely cited across the web, so strong link profiles and frequent brand mentions tend to travel together.
The AI search hub explains how links fit in, with deeper guides on getting into AI Overviews, LLM SEO, generative engine optimisation and why brand mentions now matter even without a link.
How to measure link building
Measure the outcome, not the activity. A report that lists fifty links means nothing if the target pages haven't moved.
| What to track | Where to find it | What good looks like |
|---|---|---|
| New referring domains | Ahrefs, Semrush, Majestic, Search Console | Steady growth from relevant sites |
| Rankings for target keywords | Rank tracker or Search Console | Target pages climbing over two to six months |
| Organic traffic to linked pages | Search Console, analytics | Rising clicks, not just impressions |
| Lost links | Backlink tool alerts | Few losses, replaced or reclaimed quickly |
| Profile health | A periodic backlink audit | No spikes of spam, natural anchor mix |
Links usually take weeks to be found and longer to show their full effect, so judge a campaign over months rather than days. For real-world before and after examples, see the link building case studies.
The short version
- Link building is getting relevant, trusted sites to link to you, and links remain part of Google's core ranking systems
- Every tactic follows the same loop: asset, prospect, pitch, placement, rankings
- Judge a link on relevance, real traffic and placement before any third-party score
- Work out how many links you need by comparing referring domains with the pages that rank, not by picking a number
- Paying for links that pass ranking credit is against Google's policies, so know where the line is before you buy
- Measure rankings and traffic to the target page, not the length of the link report
Start with one good asset and ten good prospects. Most link building problems are solved by doing that well before doing it at scale.