Most SaaS Google Ads accounts have the same problem: they are brilliant at producing free trial signups and mediocre at producing revenue. The bidding algorithm is doing exactly what it was told — it was told the wrong thing.
Reducing SaaS CAC is mostly a measurement exercise, followed by a keyword exercise.
Three keyword tiers, three economics
Brand terms are cheap and convert at 20%+. Defend them; competitors bid on your name. Category terms ("project management software") are expensive with mixed intent and need strong qualification. Competitor terms are the middle ground — high intent, moderate cost, and comparison pages convert them well.
Problem-aware terms ("how to track billable hours") are cheap but rarely convert directly. Run them for retargeting audiences, not for trials.
Trial or demo, not both on the same page
Self-serve trials work for low ACV products, sales demos for high ACV. Offering both on one page halves the conversion rate of each. Pick one per campaign and match it to the deal size the keyword implies — enterprise queries get demos, SMB queries get trials.
Optimise toward qualified pipeline
Feed your CRM stages back into Google Ads: qualified lead, opportunity, closed-won, each with a value. Once the account bids toward opportunities rather than signups, spend shifts away from the free-tool traffic that inflates signup counts.
In practice this is offline conversion import plus consistent identifiers between forms and CRM — the attribution and measurement layer most SaaS teams postpone.
Negative keywords that protect SaaS budgets
Block: free, open source, crack, torrent, alternative to (unless intentional), tutorial, login, jobs, careers, review (unless you own the comparison page), and any adjacent category you do not serve. Category search is noisy and broad match amplifies it.
What good SaaS numbers look like
Category clicks run $8 to $30, competitor terms $6 to $20, brand under $3. A healthy B2B SaaS account converts 2–5% of category traffic into demos and 25–40% of brand traffic into trials.
If CAC is climbing, check the mix before the bids — usually category spend has grown while brand and competitor spend stayed flat.