Domain acquisition for SEO: what 301 redirects really pass, and where Google draws the line

Buying an aged domain and redirecting it into your own site is one of the oldest moves in SEO. It is also one of the most mis-sold. Articles about it promise that a 301 redirect hands over "70 to 90 percent of the link equity" within six months, quote it as a consensus, and never give a source, because there is none. Google does not publish a percentage. What it does publish is how it treats permanent redirects, how long a move takes, and, since March 2024, a spam policy written for exactly the abuse of this tactic.

This guide sticks to what is documented: Google's own pages, read in October 2026, and the mechanics of the tools involved. Where something is a judgment call rather than a fact, it says so.

Why people buy aged domains, and the rule that now frames it

A domain that has been online for years carries links from other sites, earned when it was a real business, a real blog or a real project. A new domain has none. Redirecting the old domain into yours is how a company that buys another company usually handles the website: the old address points to the new one, and visitors and search engines follow.

The same move, done only to borrow links, is what Google targets. On 5 March 2024 Google added "expired domain abuse" to its spam policies: an expired domain bought and repurposed primarily to manipulate search rankings, with content that gives visitors little or no value. Its examples: affiliate content on a domain that used to belong to a government agency, commercial medical products on a former non-profit medical charity, casino content on a former elementary school site. Sites that violate the spam policies can rank lower or disappear from results.

The line that follows from it is practical rather than legal: the closer the acquisition looks to a real merger, the safer it is. Same subject, pages that keep answering what their old visitors came for, a redirect that makes sense to a human. The further it drifts toward "any domain with links, pointed at whatever we sell", the closer it is to what the policy describes, and the more fragile anything it brings becomes.

What a 301 redirect actually does, according to Google

Google's documentation on redirects (last updated 14 April 2026) is short and clear:

• 301 and 308 are both permanent. They tell Google the page has moved for good, and Google treats the target as the preferred, canonical version. A 308 is not a lesser 301: the only difference is that a 308 keeps the request method.
• 302, 303 and 307 are temporary. Google tends to keep showing the source URL in results. If the move is permanent, use a permanent code.
• Google gives no percentage. Nothing in its documentation says how much of a page's signals "pass" through a redirect. Any figure you read is someone's guess.

For moving a whole domain, the site move guide (last updated 20 August 2026) adds two things worth planning around. For a medium-sized site, it can take a few weeks or more before Google gradually shows the new URLs instead of the old ones, and longer for a large one. And redirects should stay in place as long as possible, generally at least one year.

One hop, permanent, to the closest equivalent

Three technical habits follow from that documentation and from how crawlers work:

• Redirect in one hop. If the old domain points to an intermediate address that points somewhere else, fix it so every old URL goes straight to its final destination. Chains waste crawling and break more easily.
• Use 301 or 308, never a temporary code, and check it after setup with curl -I: the first response should be a 301 or 308 with a location header pointing to the final URL.
• Map page to page where it matters. Sending every URL of the old site to your homepage is the lazy version. A redirect makes sense when the destination answers the same need as the source: an old article about e-commerce SEO goes to your page on the same subject, the old homepage goes to your homepage. Pages with no equivalent can go to the closest hub page, or simply return a 404 or 410 rather than land somewhere unrelated.

Why blanket redirects to a homepage underperform

When hundreds of unrelated URLs all land on one page, the redirect stops making sense to a reader, and it no longer tells a search engine where each old page's content went. Page-to-page mapping takes longer, but it is the only version where each redirect still means something. A sensible split: map explicitly the old pages that had links or traffic (an Ahrefs or Semrush top-pages report, and the old site's own analytics if you can get them), and treat the long tail in bulk.

Where acquirable domains come from

Four channels exist. They differ in price, in how much noise you wade through, and in how close the result can get to a real merger.

Public auctions and drop-catching

NameJet, GoDaddy Auctions and DropCatch sell domains that are expiring or have just been released. They are the easiest entry point and the noisiest: most of what is listed has been parked, spammed or used for something you would not want attached to your brand. Filter hard on age, on the history of the content (see the Wayback check below) and on topic before looking at any link metric.

Expired domain aggregators

ExpiredDomains.net, SpamZilla and DomCop list expiring and recently dropped domains with SEO metrics overlaid. Everyone looking for expired domains uses them, so treat them as a discovery tool: find candidates there, then bid through a drop-catching service or contact the owner directly if the domain has not expired yet.

Buying from the people who ran the business

The channel closest to a real merger is also the one fewest people use: agencies, software products, directories and blogs in your own field that stopped trading, whose founders still renew the domain. Former founders are findable through professional networks and company registers, and a direct, honest offer is the cleanest way to ask. Buying from the original owner also lets you ask the questions that matter later: what the site was used for, whether any customer claims are pending, whether the name is a registered trademark.

Brokers and private marketplaces

Brokers such as Saw.com and MediaOptions handle larger transactions. They do not find value for you; they make closing faster and cleaner on a name you already know you want, typically because you have a precise destination for it.

How to vet a domain before you buy it

Vetting is where most of the risk is removed. A domain with a bad past brings that past with it.

Content history in the Wayback Machine

Open the domain in the Wayback Machine and walk through snapshots from its first year to its last. Three questions:

• What was it about? Topic match with your site is the single most important criterion, for users, for Google, and for the expired domain abuse policy.
• Was it a real site? Real articles, team pages, contact details, or thin pages and banners.
• Did it ever change hands badly? Any period as a casino, payday loan, pharmacy or adult site, or as a page of paid links, is a reason to walk away.

The links themselves

Open the domain in a backlink tool (Ahrefs, Semrush or Majestic) and read the referring domains, not just the score. The ones at the top should be real publications, associations, partners and directories of the trade. A stable or slowly fading history is normal for a site that stopped publishing; a cliff often means links were removed or a network was taken down. Domain Rating and Authority Score are vendors' estimates, not Google metrics.

Spam in the profile

There is no official "toxicity" threshold. Google's disavow documentation says that in most cases it can assess which links to trust without help, and that most sites will not need the disavow tool; it is meant for links that have caused, or will likely cause, a manual action, such as paid links. In practice: a profile dominated by paid or spammy links is a reason not to buy, not a cleaning job.

Indexing and safety checks

Search site: followed by the domain: a domain that a backlink tool credits with many links but that has never appeared in Google deserves suspicion. Check it in Google's Safe Browsing transparency report. If the seller can give you access to its Search Console property before the sale, look for manual actions there.

Relevance to the destination

The last filter is the simplest to state: would a visitor of the old site be well served by landing on yours? A defunct marketing agency redirected into a marketing agency: yes. A fashion blog redirected into a B2B software page: no, and no metric changes that.

Legal checks before you pay

Trademarks. Search the name in the trademark registers that cover your markets (EUIPO, USPTO, INPI in France). A domain matching a live trademark exposes you to a UDRP complaint and to losing the domain.

The seller's past. If a business ran on the domain, ask in writing about pending refunds, disputes and unpaid creditors. You are buying a domain, not the company, but an angry former customer can still attach old grievances to your name.

A written agreement. Even for a small amount: the domain, the transfer method, the price, the seller's statements (owner of the domain, no pending dispute, no known trademark claim). For larger amounts, use an escrow service such as Escrow.com, which holds the payment until the transfer is complete.

Ownership history. A WHOIS history lookup shows whether the seller has owned the domain as long as they say. Someone who bought it three months ago is reselling, not handing over a business.

A redirect workflow with Cloudflare Bulk Redirects

Once the domain is in your registrar account and its DNS is yours:

1. Put the domain on Cloudflare. Change the nameservers at the registrar and add the domain to your Cloudflare account.

2. Build the mapping. Collect the old URLs from the Wayback Machine and from a backlink tool's top pages report. Write a two-column CSV, source URL and target URL, mapping each page that had links or visitors to its closest equivalent on your site.

3. Create the Bulk Redirect list. In Cloudflare, under Bulk Redirects, create a list and import the CSV. Each item takes a source URL, a target URL, a status code (301 by default) and options described in Cloudflare's parameter reference. For the pages you did not map, one item on the domain root with subpath matching catches everything else:

Source URL:            acquired-domain.com/
Target URL:            https://your-site.com/the-closest-hub/
Status code:           301
Subpath matching:      on
Preserve path suffix:  off
Preserve query string: off

With path suffix preservation off, every unmapped URL lands on the hub page itself rather than on a path that does not exist on your site. Then create the Bulk Redirect rule that uses the list and enable it.

4. Test every kind of URL. The homepage, a mapped URL and an unmapped one:

curl -I https://acquired-domain.com
curl -I https://acquired-domain.com/about
curl -I https://acquired-domain.com/blog/some-post

Each should answer 301 (or 308) with a location header on the right final URL. If a mapped URL lands on the hub, the catch-all is taking precedence: fix the list before going further.

5. Tell Google. Verify the old domain in Search Console and use the Change of Address tool, which Google reserves for moves from one domain to another. Submit your own sitemap so the destination pages are recrawled.

6. Measure, and keep the redirects. Watch impressions and clicks of the destination pages in Search Console for several months. Keep the redirects as long as possible, and at least a year, as Google recommends.

Where this leaves you

Buying a domain that belonged to a real business in your field, redirecting each of its pages to the page that now answers the same need, and keeping it that way is a normal, documented operation: Google calls it a site move. Buying unrelated expired domains because they have links, and pointing them at whatever you sell, is the practice its spam policy names. Between the two, every case is a judgment, and the honest test is the one Google itself applies: would the people who used the old site be well served by where the redirect sends them?

For the record: we have looked at this tactic for our own sites and have not bought a domain for it.