Backlink strategy: the tactics that hold up, the ones that get sites penalised, and how to vet an agency

A backlink strategy is a repeatable way of giving other sites a reason to link to you. Three families of tactic do the work: be the source, by publishing original data, a free tool or the definitive guide in your niche; be the obvious name, through press commentary, partnerships, associations and speaking; and reclaim what you have already earned, from unlinked brand mentions, broken pages that still have links pointing at them, and lost redirects. Links exchanged, bought or placed at scale to move rankings are link spam under Google's own policies, which is why the cheap options are the expensive ones.

This page covers tactic selection, risk, measurement and how to brief and vet a link building company. For the on page work that makes a link worth having in the first place, see a guide to on page SEO.

Start with what Google says, because it is specific

Google's spam policies have a link spam section, and the test it describes is intent: whether a link was created primarily to manipulate rankings. Buying or selling links for ranking purposes, excessive link exchanges, large scale article campaigns with keyword rich anchors, and automated link creation are all named. Google also publishes a page on hiring an SEO that tells site owners to walk away from anyone who promises a number one ranking. Read both before you sign anything. Quoting them back to a prospective supplier is the fastest vetting question there is.

The tactics, ranked by what they return per hour

Tactic	Effort	Durability	Notes
Original research or a data study	High	Years	The highest ceiling in link building. One survey or dataset gets cited repeatedly because writers need a number to quote
A free tool or calculator	High	Years	Works when it answers a question people ask daily. Needs engineering time and maintenance
Unlinked mention reclamation	Low	Permanent	Someone already named you. A polite email asking for the link converts well. Do this first
Broken page recovery on your own site	Low	Permanent	Find your 404s that still have inbound links and redirect them to the right live page. Pure recovery, no outreach
Press commentary and expert quotes	Medium	Long	Reply to journalist requests in your actual field, fast, with a usable quote and a credential
Partner, supplier and customer pages	Low	Long	Everyone you already do business with has a partners page. Ask
Industry associations and real directories	Low	Long	The ones with membership criteria and human review. Skip anything that lists every submission
Podcasts, panels and talks	Medium	Long	A show notes link plus an audience. Also the easiest to start this week
Resource page and broken link outreach	Medium	Medium	Works where you genuinely have the better replacement page
Guest articles on real publications	Medium	Medium	Fine when the publication has readers and an editor. A network that sells placements is a different thing entirely
Paid placements, link packages, private networks	Low	None	Named in Google's link spam policy. The cost arrives later

A strategy is the order, not the list

Most sites get the best first quarter by doing the recovery work before any outreach.

• Week one, recovery. Pull your 404s with inbound links and redirect them. Export brand mentions from the last twelve months and ask for links on the ones with none. Check that an old domain or an old URL structure still redirects.
• Week two, relationships you already have. Customers, suppliers, integration partners, your accountant, your trade body, your local chamber, the conference you sponsored. Make the list, send the emails.
• Weeks three to eight, one linkable asset. Pick a question in your industry that has no good published answer and answer it with real data, from your own operations if you have it. Then pitch it to the fifteen people who write about that subject.
• Ongoing, show up where journalists look. Set aside twenty minutes a day for journalist requests in your field. The hit rate is low and the links are strong.
• Always, internal links. The cheapest lever on the board. When you publish, add links from three existing pages to the new one, and from the new one to your money page.

How to vet a link building company

There are good agencies doing genuine outreach and digital PR, and there are resellers who place paid posts on expired domains. The two sound identical on a sales call, so ask for specifics.

• Show me five links you built last quarter, with the client page they point to. Then open the five sites. Do they have an audience, an editorial team and traffic of their own, or are they content farms in four languages?
• Do you pay for placements, in money or in product? A straight answer here tells you what you are buying. An evasive one tells you more.
• What is the outreach process, and who sends the emails? You want names, pitch templates and a target list, not a monthly quota.
• What happens to the links if I cancel? If links are removed when you stop paying, they were rented, and rented links are paid links.
• How do you report? Referring domains to specific target pages, with the page and the anchor. A spreadsheet of domain authority scores with no destination URLs is not a report.
• Red flags. A fixed number of links per month at a promised authority score, any claim to guarantee rankings, refusing to name the sites until after payment, and anchor text lists written in exact match commercial phrases.

What to measure

• Referring domains to your target pages, not to the homepage. Links to the page you want to rank are the ones doing the work.
• Whether a buyer could have read it. One link on a publication your customers actually read beats thirty on sites nobody visits.
• Referral traffic and enquiries from the link, which is the test that no algorithm change can take away.
• Movement on the target page in Search Console, read over eight to twelve weeks rather than week to week.

Authority scores from third party tools are useful for sorting a prospect list quickly. Keep them as a filter, never as the objective, since they are each vendor's own model rather than anything Google publishes.

Where people get stuck on backlink strategy

How many backlinks do I need to rank?

There is no threshold. Look at the pages currently ranking for your query, count their referring domains, and treat the middle of that range as your working target. For a local service page that is often a handful. For a competitive commercial term it can be hundreds.

How long does a new link take to have an effect?

Google has to crawl the linking page first, which is days to weeks, and the ranking effect accumulates rather than switching on. Judge a campaign on a quarter, and judge a single link on whether it sent you a customer.

Are guest posts still worth doing?

On publications with real readers and a real editor, yes, and treat them as audience building that also earns a link. Networks that sell placements across hundreds of thin sites are the thing Google's link spam policy describes, so keep the two clearly separate in your own mind.

Should I buy backlinks?

No. It is explicitly named in Google's spam policies, the sites involved tend to be sold to everyone in your sector, and the links disappear when the seller stops paying for hosting. Put the same budget into one piece of original research and the outreach to promote it.

Do I need to disavow bad links?

Rarely. Google ignores the great majority of spam links on its own, and the disavow tool is for the case where you have a manual action in Search Console or you know you were responsible for the links. Negative SEO panic has cost more sites more traffic than negative SEO has.

What about nofollow and sponsored links?

Mark paid and sponsored links with rel="sponsored" and user generated links with rel="ugc". Google treats these as hints rather than as strict instructions, and labelling honestly is what keeps a site out of the link scheme conversation entirely.

Links that earn their place inside an answer

Of the tactics ranked above, the durable ones, original data, real press, partnerships, produce pages that other writers cite. The paid link produces a page nobody cites. Whether an assistant reads the pages you earned is a thing you can check rather than assume.

Ask your category question and open the sources shown. Count how many are earned links of the type you are building. AI Knows Us lists the sources behind each answer.