Microsoft Ads UET tag: install it before launch, even with no remarketing budget yet?

When you move a Google account over, most people focus on campaigns and bids and leave the UET tag for later. I'd install it on day one, before any spend. Microsoft's audience pool is much smaller than Google's, so a remarketing list built from the first few weeks of traffic is often what makes month two workable. Wait until you "have budget" and you start with an empty list, then lose another month while it fills.

The counterargument is fair: if you never plan to run remarketing, the tag is just extra page weight and one more line in your consent banner. But that's a reason to settle your audience plan now, not to skip the tag. Has anyone seen list sizes hold up on a low-traffic B2B site?

I'd lean on the conversion data more than the remarketing list. On a low-traffic B2B site the list may never hit Microsoft's minimum audience size, so building a plan around it is a gamble. UET is also how Microsoft learns which clicks turn into leads, and that signal feeds bidding from the first week. You need it even if you never remarket, so the consent banner cost is the same either way. Roughly how many unique visitors a month does the site get?

Agreed, the conversion signal matters more than the list. I'd install UET before the first click and decide on remarketing later. The tag only starts building history the day it goes live, and you can't backfill that data afterward.

Agreed on the conversion signal. Whether the tag is worth installing comes down to one thing: can you actually count a conversion on the site? If leads come through a contact form that redirects to a thank-you page, UET records that without any fuss. If they come through a phone number, a chat widget, or a form that never changes the URL, the tag alone tells Microsoft almost nothing. In that case the conversion event is the real work, and the tag is the easy part.