Titles and rel-alternate-hreflang annotations

In my last webmaster office hours hangout I got an interesting question: When a webmaster uses rel-alternate-hreflang annotations to mark up a cluster of equivalent pages that target different language-country combinations, can the titles be different for each country?

The answer is yes, use a title that makes sense for your users and your site.

Let's take an example to illustrate this. Suppose we have these two English language pages selling the same widget, one for the US and one for the UK:


Let's say they both use the same product description, product image, etc, so their content is considered substantially the same thing (aka "duplicate content").

But the pages are slightly different: The US page has the price in US$, the UK one in GBP and each page has a different local customer service number and delivery info.

The idea of rel-alternate-hreflang is to help you signal to our algorithms that although these two pages have substantially the same content, the small differences between them are still important. Specifically, the small differences are relevant for users of a specific language (and in a country). By the same logic, the title can be different too. 
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