503 is the SEO-friendly way to take a site down briefly. When you return 503 during maintenance, ideally with a Retry-After header, you tell Googlebot to come back later instead of treating pages as broken — protecting your index while you work.
The opposite mistake is serving a 500, a redirect to a maintenance page, or a 200 "we'll be back" page during downtime. Those confuse crawlers and can cost rankings. A correct 503 keeps things clean.
It's only meant to be temporary. If a 503 persists for a long time, Google may eventually treat affected URLs as errors and drop them, so resolve overloads and keep maintenance windows short. Recurring unplanned 503s indicate the server needs more capacity.
FAQ
Frequently asked questions
Yes. A 503 with a Retry-After header is the correct signal for planned downtime — it tells Google the outage is temporary so pages aren't dropped. Avoid returning 200 or 500 during maintenance.
