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Direct traffic is almost always going to be one of your top traffic sources. There are a number of reasons people end up in this bucket. They open a new browser and go straight to your site. There is no referrer to track here and is what people think of when they see the Direct bucket. A user was on your site, but kept the tab open. Hours or days later, they get back to the tab and engage again. That is a direct session since there was not a referrer. A user is blocking the information of the referring site through their own computer settings. You can't control this. A mistake happens on the referring site's side. You can't see this either or do anything about it. A company I worked for saw a spike in Direct traffic that ended up being Snapchat ads once. There wasn't much to be done. A mistake is happening in your setup of Google Analytics. This is unlikely, but if you have a custom setup, talk to the person that is in charge of that on your site. There are more instances here: https://moz.com/blog/guide-to-direct-traffic-google-analytics and some tips on cleaning this up if you suspect some traffic isn't being tagged correctly.