According to Google’s John Mueller, many times it doesn’t matter if you use absolute or relative URL for internal linking of pages. The topic was come up in the latest Google Webmaster Central Hangout.
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Mueller explains two conditions when absolute and relative URL might or might not come into existence.
Condition 1: Perfect Site Structure
When a website has a perfect site structure, which means the website owner has implemented canonicals and a single uniform domain in the right way then it doesn’t matter if your use absolute or relative URL. After this Mueller recommends the owner to use whatever is easier for them.
Condition 2: Imperfect Site Structure
If the website is not perfect in site structure then, in that case, the website owner must use the absolute URL. Using of absolute URL will give some sort of benefits to the website owners. It makes it easier for Google to return to the preferred page.
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