Quick answer: A 301 error is not really an error. HTTP 301 is a permanent redirect status code that tells browsers and search engines a URL has moved for good, so traffic, links and ranking signals should transfer to the new address instead.
People search for “301 error” because their browser, crawler tool or Google Search Console flagged a 301 and it looked like a problem. It usually isn’t. Errors live in the 4xx range (404 Not Found) and the 5xx range (500 Server Error). The 3xx range is redirection, which is the web working as designed. When a server returns 301, it is saying: this URL is retired, use this other one from now on.
A 301 only becomes a real problem in three situations: it points somewhere wrong, it loops back on itself, or it quietly drops the tracking parameters that tell you where your leads came from. The last one is the expensive version, and it is the one most teams never check.
Why a 301 error matters for traffic and ad spend
On the organic side, the 301 is how you keep the rankings you already paid for with time and content. Google’s own migration guidance is blunt about this: permanent redirects such as 301 and 308 do not cause a loss in PageRank, so a clean one-to-one redirect map is what carries your authority from old URLs to new ones (Google Search Central).
Get the map wrong and the safety net disappears. Redirecting a pile of old URLs to one irrelevant destination, usually the homepage, can be treated as a soft 404, which means Google ignores the redirect and passes nothing (Google Search Central). Remove the redirects too early and you get the same result: Google recommends keeping 301s in place for at least a year so its systems see the change enough times to record it as permanent (Search Engine Journal, on John Mueller’s guidance).
On the paid side, the damage is faster and harder to spot. A 301 that does not forward the query string strips the gclid and UTM parameters off your ad clicks, so paid conversions land in your reports as direct traffic and your campaigns look worse than they are (Adnan Agic, GCLID stripped by redirects). Smart Bidding then optimises against numbers that were never true.
There is a policy angle too. Google Ads has historically disapproved ads whose final URL redirects the user to a different domain under its Destination mismatch policy, and from July 2026 that is permitted only in certain cases with prior approval (Google Ads Policy Help, Search Engine Roundtable, June 2026). A redirect nobody documented can take a whole account offline.
301 vs 302 vs 307 vs 308
All four are redirects. They differ in what they promise about permanence and what they preserve. Use the status code that is technically true, because Google treats 301 and 308 as permanent and deliberately keeps the old URL in its index when you use a temporary redirect (Google Search Central).
| Attribute | 301 | 302 | 307 / 308 |
|---|---|---|---|
| Meaning | Moved permanently | Found, moved temporarily | Strict temporary (307) / strict permanent (308) |
| What Google does | Indexes the new URL, transfers signals | Keeps the old URL in results | 307 behaves like 302, 308 behaves like 301 |
| Ranking signals | Passed, no PageRank loss | Stay with the original URL | 308 passes signals like a 301 |
| Request method | Can convert POST to GET | Can convert POST to GET | Method and body preserved |
| Browser caching | Cached hard, a mistake sticks | Not cached by default | 307 not cached, 308 cached |
| Use it when | URL, domain or protocol changed for good | Page is down, out of stock, A/B test | Forms and APIs where POST must survive |
How to diagnose and fix a 301 error
Work through these in order. Most “301 errors” are solved in step 2 or step 4.
- Confirm it is actually broken. Run the URL through a redirect checker or your browser’s network tab. A single 301 landing on a working page with a 200 status is healthy. Only a loop, a chain, a 404 at the end, or a lost parameter needs fixing.
- Kill redirect loops. If you see ERR_TOO_MANY_REDIRECTS, two rules are fighting: usually an http to https rule, a www rule, and a trailing-slash rule stacked on top of each other. Rewrite them as one rule that goes straight to the canonical version.
- Flatten chains. Googlebot follows up to 10 hops, but Google advises redirecting to the final destination directly and keeping any chain to no more than 3 (Google Search Central). Every extra hop adds load time before a paid visitor sees your offer.
- Force the query string through. In Apache, add the QSA flag: RewriteRule with [R=301,L,QSA]. In Nginx, pass $is_args$args (or use $request_uri) in the return 301 line. Then test by loading your live landing page with ?gclid=test on the end. If the parameter survives the redirect, tracking survives.
- Map one to one, never to the homepage. Each retired URL points to its closest real replacement. If there is no replacement, let it return a 404 or 410 honestly.
- Update internal links, sitemap and ad URLs. Point menus, internal links, XML sitemaps and every Google Ads final URL at the destination, not the redirect. Leave the 301 in place for at least a year for outside links.
What a stripped parameter actually costs: a Mumbai D2C brand spends ₹4,00,000 a month on Google Ads and gets 500 leads, so its true CPA is ₹800. During a site tidy-up, the landing page URL is 301’d to a new path without QSA, so the gclid is dropped and only 150 leads still carry ad attribution. Google Ads now reports a CPA of ₹2,667, tCPA bidding pulls back on the best campaign, and the other 350 leads show up as direct traffic. Nothing changed in the market. One redirect rule changed the reported truth.
Common mistakes
- Treating the 301 as the bug and deleting it. Removing a redirect turns a working URL into a 404 and throws away the links and history pointing at it. Fix the destination instead of removing the rule.
- Dumping dead URLs on the homepage. Mass redirects to one irrelevant page can be read as soft 404s, so no signals transfer and users land somewhere that does not answer why they clicked.
- Using a 302 for a permanent move. A temporary redirect tells Google to keep the old URL in its results, so the new page never fully takes over. Long-lived 302s are one of the most common causes of a migration that “lost rankings”.
- Ignoring the query string. Most redirect rules developers write do not forward parameters by default. Attribution, call tracking and email campaigns all break silently, and the dashboards still look plausible.
- Pointing ads at a redirect. Sending paid traffic through a hop adds latency, risks a Destination mismatch disapproval, and puts your tracking one rule away from failure. Ads should point at the final URL.
Frequently asked questions
Is a 301 an error?
No. A 301 is a successful redirect response, not an error. It sits in the 3xx redirection range, while genuine errors sit in the 4xx range (like 404 Not Found) and the 5xx range (like 500 Internal Server Error). A 301 only signals a problem if it loops, chains, ends on a broken page, or drops tracking parameters.
Does a 301 redirect hurt SEO?
A correctly configured 301 does not hurt SEO. Google states that permanent redirects such as 301 and 308 do not cause a loss in PageRank. Rankings drop when redirects point to irrelevant pages, sit in long chains, or get removed too early, not because the 301 status code itself was used.
How long should I keep a 301 redirect in place?
Google recommends keeping a 301 in place for at least one year. Its systems need to see the redirect several times across multiple crawls before recording the change as permanent, and external links to the old URL can keep sending traffic for years. On a site with valuable backlinks, leaving them permanently is safer.
What causes a 301 redirect loop?
A redirect loop happens when two or more rules send the request back to a URL that has already been visited. The usual culprits are conflicting http to https, www to non-www, and trailing-slash rules, or a CMS-level redirect fighting a server-level one. Consolidate them into a single rule that resolves straight to the canonical URL.
Do 301 redirects break Google Ads and UTM tracking?
They can. If the redirect rule does not forward the query string, the gclid and UTM parameters are stripped and conversions are attributed to direct traffic instead of your campaigns. Add the QSA flag in Apache or pass the arguments in Nginx, then test by loading the page with ?gclid=test appended.
How Uginix helps
Redirect audits are part of how Uginix protects both organic traffic and ad attribution during a redesign, a domain change or a landing page rebuild. We map old URLs to real replacements, flatten chains, verify that gclid and UTM parameters survive every hop, and repoint ad final URLs so campaigns never run through a redirect. See our SEO, GEO and analytics services, or the landing page checklist we run before any campaign goes live. Not sure where your ad spend is leaking? That is exactly what our growth audit finds.
Related terms
- 404 Error, the status code for a page that does not exist, and the honest answer when content is genuinely gone.
- Canonical URL, the single preferred version of a page that Google should index when duplicates exist.
- Redirect Chain, two or more redirects stacked between the requested URL and the final page.
- GCLID, the Google click identifier that links an ad click to a conversion, and the first thing a careless redirect destroys.
- Attribution, how credit for a conversion is assigned across the channels that touched it.
Sources: Google Search Central, Redirects and Google Search, Google Search Central, Site moves with URL changes, Google Ads, Destination requirements policy, Search Engine Journal, Adnan Agic on GCLID loss.