X ads are worth testing for B2B SaaS founders who need cheap top-of-funnel reach, not for founders expecting a clean lead-generation channel. The CPC is roughly a tenth of LinkedIn's, but the conversion data you'll see in the ads dashboard is close to fiction, and that gap is what actually determines whether the channel works for you.
I ran X ads for two different B2B SaaS products over the last year. Both times the dashboard told a story that didn't match what actually happened in the pipeline, and both times the fix wasn't a better campaign. It was measuring the right thing.
The cost case for X ads
X's average CPC sits around $0.74, against $5 to $8 for LinkedIn. CPM tells the same story: about $5.80 to $6.46 on X versus roughly $34.50 for LinkedIn's B2B tech targeting. If you're paying for impressions or clicks, X is not close, it's a different order of magnitude.
The catch is what those clicks do next. LinkedIn's targeting runs on real job titles, company size, and seniority pulled from a professional graph. X's targeting runs on interests, follower lookalikes, and keyword conversation matching, which is a much blunter instrument for reaching a VP of Engineering at a 200-person company. You're buying cheap reach into a roughly-right audience, not precise reach into an exact one.
That trade only makes sense if you're honest about what stage of the funnel you're buying for. Cheap awareness against a loosely-targeted audience is a real asset early on. Cheap awareness mistaken for cheap lead generation is how founders burn $3,000 and conclude the channel doesn't work.
The measurement problem nobody tells you about
Here's the part that actually decides whether X ads are worth it, and it has nothing to do with the ad itself: the conversion number in your X ads dashboard is undercounting what's really happening, often badly.
Pixel-based tracking across paid social platforms is losing 20 to 40% of real conversions to ad blockers, Safari's Intelligent Tracking Prevention capping cookie life at 7 days (24 hours for click-ID parameters), GDPR consent declines, and cross-device journeys where someone sees your ad on their phone and buys on a work laptop three days later. X never built the same first-party tracking infrastructure LinkedIn and Meta have, so if anything its native attribution is on the weaker end of an industry-wide problem, not an exception to it.
What that means practically: if you judge an X ads campaign purely by the "conversions" column, you are judging it by a number that's missing a third to a half of what it should show. Most founders see a low number, assume the channel failed, and kill it before it had a fair trial.
The fix is to stop asking the pixel a question it structurally can't answer, and build two or three proxy signals instead:
- Branded search lift. Pull weekly branded search volume (Google Search Console or Ahrefs' brand tracking) for the four weeks before your campaign and the four weeks during it. A real lift, even 15 to 20%, tells you the ad is registering with people who don't click.
- Direct traffic delta. Segment GA4 direct traffic by week against your ad spend calendar. People who see an ad, don't click, and type your URL later show up here, not in the ads dashboard.
- Sales-cycle self-report. Add one field to your demo booking form: "How did you hear about us?" It's not scientific, but a founder running $2,000/month in X ads who sees "saw you on Twitter" appear on 3 of 20 demo calls has more signal than a pixel that says zero.
None of these replace real attribution. They exist because real attribution on this channel is currently broken for everyone, and a proxy you trust beats a precise number you shouldn't.
What actually works when you run it
The founders getting real value from X ads are almost never running pure cold-acquisition campaigns. The pattern that works is retargeting people who already followed your account, engaged with a founder's organic posts, or visited your site, then promoting a specific piece of proof (a customer result, a product demo clip, a comparison post) rather than a generic "book a demo" ad.
This matters because X's own audience behavior skews toward people scrolling for opinions and news, not people in active buying mode. An ad that interrupts that mode with a hard pitch gets ignored. An ad that continues a conversation someone already opted into, by following you or engaging with your content, converts at a meaningfully higher rate because the trust groundwork is already done.
Budget-wise, this means splitting spend differently than you would on Google or LinkedIn: 60 to 70% into retargeting and lookalikes built from your existing audience, and the remaining 30 to 40% into a tightly-defined interest/keyword test, capped and reviewed weekly rather than left to run.
The 30-day move
Don't start with a campaign. Start with $200 and one goal: build a retargeting audience from your last 90 days of site visitors and X profile engagers. Run a single ad promoting your strongest piece of proof against that audience for two weeks, tracking branded search and direct traffic alongside the dashboard's own numbers. If the proxy signals move and the dashboard doesn't, you've confirmed the channel is working and the pixel is lying to you. If neither moves, you have your answer without having spent the $3,000 most founders waste finding out the hard way.
Frequently asked questions
Are X ads cheaper than LinkedIn ads for B2B SaaS?
Yes, substantially. X's CPC averages around $0.74 versus $5 to $8 on LinkedIn, and CPM is roughly six times lower. The tradeoff is targeting precision, not just price.
Why do X ads show fewer conversions than they actually generate?
Ad blockers, Safari's Intelligent Tracking Prevention, GDPR consent declines, and cross-device buying journeys cause pixel-based tracking industry-wide to undercount real conversions by 20 to 40%, and X's attribution infrastructure is weaker than LinkedIn's or Meta's.
What's a good proxy metric if I can't trust the X ads dashboard?
Branded search volume lift, direct traffic increases during campaign windows, and a simple "how did you hear about us" field on your demo form all catch conversions the pixel misses.
Should a B2B SaaS founder run cold-acquisition X ads?
Generally no. Retargeting people who already follow your account or visited your site converts far better than cold interest-based targeting, because X's audience is in browsing mode, not buying mode.
How much budget do I need to test X ads properly?
$200 to $500 over two weeks is enough to run a single retargeting campaign and read the proxy signals. You don't need a large budget to get a real answer, you need the right things to measure.
Testing a new paid channel always costs something. The founders who come out ahead are the ones who spend that cost on the right question, whether the channel reaches real buyers, instead of the wrong one, whether a pixel that was never built to see the whole picture says it worked.