One of the websites I run different SEO theories on was put down due to high traffic in the past few days. I thought, being my little guinea pig, I would rise to the occasion and document any changes a website undergoes, when concerning SEO, over the course of 3-4 days of downtime. Below is a screenshot of the downtime in progress, with today being my third (and final) day of downtime: Now obviously without a website to display, Google would assume that perhaps the resource is gone for good and may negatively impact their SERPs as a result. Did they? No. I'm actually doing better in SERPs right now for some of my terms than I was before the downtime. And my logs even show Googlebot crawled the pages that were down and had error messages on them! My best best bet would be to say that it's perfectly fine to have up to 5 days of downtime and not notice too much effect, although anymore and I'd say there is a bit of repercussion in store. Bottom Line: If your website is down for a few days for maintenance or due to a host switch, don't fret! Google allows for a few days of downtime because hey, we can't possibly have a server with 100% uptime. Now you can breathe a sigh of relief
Yeah it depends, i was down for 4 days and i didnt budge for any keywords. Some fairly competative such as #12 for "SEO", yet another site i have was down 3 days and traffic plunged for weeks afterwards. Site authority seems to have an effect on downtime tolerance.