Merging two sites into one

Selected answers from the Dumb SEO Questions Facebook & G+ community.

• 
  Michael Martinez: There are always potential downsides. Don`t fall prey to Paralysis by Analysis.
  
  If you can move content from the site going away to the site remaining, do so and redirect the old URLs.
  
  If you can redirect old URLs on the site going away to comparable URLs on the site remaining, do so.
  
  If don`t have comparable content on the site remaining for URLs on the site going away, create a page on the site remaining explaining that the two companies have merged and redirect whatever wasn`t redirected somewhere to that page.
  
  So ...
  
  Site A (10 pages) going away, site B (10 pages) remaining:
  
  A.1 -> B.11A.2 -> B.2A.3..A-10 -> B.12
  
  B.12 says, "Hey, we merged A with B"
  
  
• 
  Richard Hearne: Yes, there are no site migrations without risk.
  
  
• 
  Bill Hartzer: There`s always some risk when you do a domain migration, but there are tons of things you can do to minimize risk.
  
  I`m not sure if you mean that the two sites are combining and moving to another new domain? Or is just one site moving to the other site?
  
  Keep in mind that you need to make sure that you don`t combine processes so to speak. Don`t try to move the content and 301 redirect all at the same time. It gets too messy and you`re setting yourself up for issues.
  
  Instead, do it in parts--over time.
  
  Typically I recommend moving the content first, from one site to the other. 301 redirect those pages that you move. Most likely there are going to be duplicates, and some pages won`t need to move. Keep the site`s that moving live (the home page and pages that aren`t going to move).
  
  Then, later on (as long as you can drag it out, let`s say a month or two), then do the domain redirect. Content moves first, then at a later date you should move the domain. Don`t try to move the domain and the content all at once.
  
  I wrote a lengthy article about domain migrations and there`s a section on moving one domain to another that you may find helpful: https://www.oncrawl.com/technical-seo/domain-migration/
  
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