If you are planning to move an old website to a new domain name then conventional wisdom says to redirect the old domain name to the new so that you can capture visitors still attempting to visit that old website. Sometimes I do recommend going against this conventional wisdom, but there is one instance when redirecting an old name just doesn’t make sense. If your old website isn’t getting any traffic, or the traffic that it does get is so small that you can’t justify the $10/year expense to hold onto it, then you might as well just let the old domain expire. The exception in this case is if the domain name is one that you want to hold onto and you plan to develop later for re branding purposes. Otherwise, a website with no traffic or low traffic isn’t going to benefit you with a redirect.
How long you’ve had the old domain does make a difference, however. If it’s a ten year old domain then it’s valuable even without the traffic (though a domain that old likely has a good stream of traffic). If it’s a fairly young domain then redirecting might not make sense.
Another consideration is how many links you have pointing to that domain name. If you’ve engage in a strong link building campaign and you have several thousand inbound links to that domain, but those links aren’t generating traffic, you might still consider a redirect. Many links sit in a dormant state for months or years before they start sending quality traffic. That’s because a new website has not built up its reputation yet, but as it grows and increases its own reputation among its target audience, that audience will come to trust it more and visitors will click on that’s website’s links more often. So just because you have links that are not generating traffic today does not mean they won’t be generating traffic a year or two years from now.
Even when considering whether to redirect your traffic from one domain to another, you’ve got to think long term. In most cases, a redirect can be beneficial, but there are times when it won’t hurt you to let your domains expire.