Three reasons to use a www subdomain for your primary domain.

Back in the infancy of the web, ‘www’ was an almost ubiquitous subdomain.

Its use as a subdomain was mainstream throughout the 90s and into the 2000s. Initially conceived to distinguish “WorldWide Web” servers from other servers (for example ftp), it also served to signal to readers potentially unfamiliar with the concept that a word in text/an advert, was the address of a website.

Nowadays, the “www” part is becoming less and less common, both in print and online, with ever-increasing numbers of site owners choosing to drop the www prefix and have their domain apex their primary url instead.

But are there reasons for or against this, or is it simply user preference?

Does www matter?

Is it even important? Does it make any difference? And who cares anyway if we just redirect the alternative anyway?

As consumers have become more familiar with the concept of a domain name, the use of the www to signal it has started to seem redundant, old fashioned even. This has presumably been the driving force behind the move toward cleaner, more modern looking naked apex domains.

The choice appears to be purely aesthetic - in some circles there’s a belief that omitting the www in a domain has SEO benefits, but as is so often the case with SEO “tricks”, there’s no evidence actually supporting this.

Ultimately, there’s no technical reason to favour www or not, at least as far as either the Domain Name System (DNS) or the browser are concerned.

Yet I believe I can offer three solid, demonstrable, reasons to prefer www over non-www domains.

Reason one: CNAMEs

The apex domain, according to the DNS specification, should not allow the use of CNAMEs.
A CNAME record identifies the origin server, not by IP address as is the case with an A record, but by domain name.

What this means in practice, is that if you wish to implement a Content Delivery Network (CDN) or other service that gives you a domain name for your distribution rather than an IP Address (as AWS CloudFront does) you may struggle.

The majority of nameservers simply cannot or do not allow implementing this on your domain root, though with a few (for example AWS Route53 and CloudFlare ) it is possible.

In order to use a domain name based CDN on the root, you may need to change your entire nameservers to one which will support it.
Nobody wants to change nameservers if it’s avoidable, for future compatibility - www is the way to go.

Reason two: Security

Your apex domain is of utmost importance to your business. It’s used to configure corporate email, sign certificates, authenticate with productivity suites and many other business critical tasks.

Ideally your name server will allow you to configure what records, and record types, users can edit.
In this case, having www as your primary web domain is an opportunity to implement stricter access control, preventing a user from accidentally (or maliciously) changing adjacent records.

For example, with AWS Route53, in IAM we are able to assign users permission to only edit certain records of a domain.
Thus we are able to give developers responsibility for configuring DNS on www records only, allowing them access to make necessary changes (for example authenticating via TXT records with third parties), whilst withholding the ability to make changes to the root domain, which could cause terrible damage (for example wiping out all email access).

Reason three: Convention (and new tlds)

The final reason is not technical, nor security related, it’s simply convention.

In an increasingly globalized world, and with the introduction of so many new top level domains (including custom TLDs for those with deep pockets), consumers are still frequently confronted with unfamiliar url structures, for example food.delivery or unterkunft.berlin, where the inclusion of www would serve to clarify that it’s a domain name and not an unknown word or typing error.

Users won’t be surprised or turned off by seeing a “www” in the address bar.
In fact they may never even be aware of its existence, as some browsers, such as Chrome, automatically hide the www subdomain in the address bar.

Conclusion

Maintaining ‘www’ in your web address offers real benefits with no significant downsides and no effect on search engine performance.
It simplifies DNS management, enhances security, and fits with user expectations.

Changing to a ‘www’ subdomain later can be complex and disruptive, and migrating content can have a (temporary) effect on SEO, so it’s wise to start with it unless there’s a compelling reason not to.

And if marketing still prefers the more modern, clean looking naked url, they can simply advertise the apex domain, allowing it to seamlessly redirect visitors to the www subdomain.