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There are definitely pros and cons of both approaches. I will say that as someone who currently manages 5 different regional variations of a site, no matter how well we implement our hreflang tags and canonical tags, etc. the search engines still don't index us exactly the way we want them to. That has been my experience elsewhere too. In theory, you should be able to maintain two very similar, or even identical sites, and as long as you properly implement hreflang and canonicals, you should be able to target one site to US and the other to UK. But in practice, I've found that even with these things well implemented, you end up with some pages from each site being served as results in the wrong country. So, I think it depends on how significant that impact is to you. In the case of the sites I currently manage, it is very significant as our product assortment, inventory levels, fulfillment options, etc. are different in each region. So, when a customer clicks through to the wrong region's page, and doesn't follow the suggested geo-ip-based guidance we provide when we detect that, they have a bad experience and we lose customers. In the case of the sites I manage, it is not an option to consolidate into a single site/page across these regions, because we operate independently in each country with different products, inventory, prices, etc. If that's the case for you as well, then I would recommend to do your best at properly implementing hreflang and canonicals, and just recognize that the search engines won't perfectly respect your directives for indexation. But if, on the other hand, your business could serve the same content to both regions, you would avoid those indexation pitfalls by consolidating on one domain. In your case, there is also another factor, which is the perception (in both markets) of the .co.uk domain as being local for UK. So, that helps you in the UK, and hurts you in the US. The .com domain will be better in the US, and not necessarily problematic in the UK, but also would lose some of the local credibility that your .co.uk domain has there. So, that's another consideration.

Thanks for the advice.

Hi there! I'm assuming that you're seeing the traffic loss in your on-site analytics as well as in tools like SEMRush (because if not my first port-of-call would be to check your GA/similar to make sure this isn't just SEMRush seeing only part of the picture). The spam could be a factor but I think you've already addressed that. It could be worth bearing in mind that there was a core algorithm update in May so that could be a factor in the traffic change. However, a couple things interest me here. One is that you mention you've been investing less into this site - this could simply be a matter of the site being out of date and no longer a good result. The other interesting point is you mention "the next site is here". If you have been building another site targeting the same keywords and using roughly the same content, it could just be a matter of the new site taking the old site's rankings, particularly if the new site has had more recent investment. If the new site is targeting the same things as the old site, it'd probably be a good idea to redirect the old site to the new site to make sure that you have one site that's ranking on page 1 rather than two sites that are ranking page 2 and below. If the new site is something very different then I think it comes down to how willing you're willing to invest in the old one. If it's worth the time, the next thing I'd do is look at: GA to see if any pages were particularly badly hit Search console to see if there were any topics which were particularly badly hit Recent dev changes to make sure it's not a tech issue The specifics of that core ranking update (article linked above) to see if any themes jump out to you. If it seems to be sitewide then it's possible it's a dev/algorithm update issue and I'd focus on improving overall site quality. If it's localised on specific topics/pages then I'd start by focusing on how I can update that content specifically. For more specifics, this blog post by Dom Woodman is a pretty good resource. Hope that helps!