As with on-page SEO, I will talk about factors that are known to impact rankings directly and factors that don’t but otherwise can get you more visibility and organic clicks. 

Backlinks

Backlinks are the foundation of Google’s PageRank, a mathematical formula that judges the “value of a page” by looking at the quantity and quality of other pages that link to the said page. Along with search intent, backlinks are one of the most critical ranking factors.

Generally speaking, the more backlinks (from unique websites) a page has, the higher its chances of outranking its competitors on the SERPs.

And also, the more backlinks a page has, the more the amount of organic search traffic that lands on that page:

But not all backlinks will impact your rankings equally. You can judge a backlink by these six traits:

1. Authority – If we think of links as votes, then pages with more votes will pass a stronger vote to other pages.
2. Relevance – Here’s how Google puts it: “If other prominent websites on the subject link to the page, that’s a good sign that the information is of high quality.”
3. Anchor text – Like internal links, the anchor texts of backlinks help Google understand the context of the target page.
4. Follow vs. nofollow – “Nofollow” is an attribute that tells Google not to take a link into account for ranking purposes. The “follow” attribute is its opposite. Generally, the “followed” links will have more impact. All links are “follow” by default unless specified differently.
5. Placement – Links that have a higher chance of being clicked (e.g., links in the content, links placed higher on a page) will likely pass more authority.
6. Destination – Links can increase the ranking of the specific page that they link to. But you can pass some of that link equity to other pages through internal linking.

NAP citations

NAP (name, address, phone) citations are online mentions of your business that display your business name, address, and phone number.

NAP citations are probably a ranking factor that counts for localized organic search results (learn more here and here). However, they may not carry a lot of weight:

Apart from the possibility of helping you rank on the SERPs, NAP citations will definitely help users find your local business. So here’s a quick list of good practices you can follow:

• Get listed with big data aggregators – For example, Foursquare. That’s where a lot of local data providers get their data.
• Submit to the big players – These are Apple Maps, Yelp, Bing Places, Facebook, etc.
• Submit to other popular directories in your local area and industry 
• Keep your citations consistent – You should also align them with the guidelines (like this one from Google).

Google Business Profile (previously Google My Business)

Whether a Google Business Profile (GBP) is a ranking factor is not even the right question here. The GBP is simply the requirement for getting featured in Google’s map pack.

For the record, a map pack shows GBPs close to the area relating to your search query (or based on your location). Search results located below the map pack are called localized organic results.

Map pack showing GBPs of vets in Mountain View.

Does a GBP affect rankings of the results found below the map pack? Most SEO professionals say “no.”

But on the whole, if your business operates locally, you will definitely want to get a GBP. It allows Google to display your business in the map pack, and it makes it easier for customers to find you and get in touch.

On top of that, a GBP helps with getting reviews from customers, which is next on our list.

Reviews (and ratings)

Let’s look at another factor that impacts the map pack: customer reviews.

Here’s probably the most accurate way of explaining this: Customer reviews are a ranking factor impacting the order of results in the map pack, but they probably bear little importance for localized organic results.