SaaS is the category where Google Ads looks like it is working long before it is. Trials are easy to buy. Trials that convert to paid, stay past month three and cover their acquisition cost are not. An account optimized toward signups will hit its targets and lose money for a year.
Everything in a SaaS account follows from one number: how long it takes a customer to pay back what you spent acquiring them.
Bid against payback, not against a cost per lead
Take your average revenue per account per month, multiply by gross margin, and divide your acquisition cost by that. The result is your payback period in months.
| CAC | Monthly gross profit per account | Payback | Verdict |
|---|---|---|---|
| $300 | $40 | 7.5 months | Healthy for most SaaS |
| $900 | $40 | 22 months | Only works with very low churn |
| $900 | $150 | 6 months | Comfortable |
| $2,000 | $150 | 13 months | Needs enterprise retention |
What this means for you: two SaaS companies with identical cost per trial can be in completely different positions depending on price point and churn. Anyone proposing a cost per lead target without asking about churn is guessing.
For reference, the all industry benchmarks across 13,474 US search campaigns were $5.42 per click, $66.69 per lead and an 8.18% conversion rate, per WordStream. B2B software usually sits well above that on cost per click.
Optimize toward qualified, not toward signups
Free trial signups are the easiest conversion in SaaS and the most misleading. Free email addresses, students, competitors and people who will never activate all convert at the same rate as real prospects.
Feed the funnel back in stages:
- Signup as a secondary action. Watch it, do not bid on it.
- Activated, meaning they completed the action that predicts retention in your product. This is usually the right primary conversion.
- Paid conversion, with a value reflecting expected lifetime, not the first invoice.
Activation is the one most teams skip and it is the most useful, because it arrives in days rather than months and still correlates with revenue. From 15 June 2026 Google moved offline conversion imports to the Data Manager API and blocked them in the Google Ads API, so check any older integration. Our guide to conversion tracking covers the setup.
Low volume means Smart Bidding may not work yet
This is the practical constraint most SaaS accounts hit and few agencies mention.
Google publishes conversion thresholds for its bidding strategies. Target ROAS on Search and Shopping requires at least 15 conversions in the past 30 days, and Google recommends evaluating Target CPA over 30 days including at least 30 conversions.
If your paid conversions are five a month, no automated strategy has enough to learn from. The honest answers are to optimize toward activation instead, which produces more events, or to consolidate campaigns so the data pools rather than splitting across six. Our post on bidding strategies covers the thresholds by campaign type.
Category terms, competitor terms and alternative terms
SaaS search splits into three useful groups and they behave very differently.
- Category terms like “project management software”. High volume, expensive, and full of researchers. Worth it once tracking is honest, not before.
- Competitor terms. Expensive, low Quality Score, and genuinely effective when you have a clear point of difference. Expect retaliation.
- Alternative and versus terms. “X alternative” and “X vs Y” are the best value in the category. The searcher is actively switching and the volume is cheap.
The third group is consistently under exploited. Someone searching for an alternative to a competitor has already decided to leave.
The negatives that matter in SaaS
- Free and open source. Free forever, open source, crack, torrent, unless you have a genuine free tier you monetise.
- Careers. Jobs at, salary, engineer hiring, internships.
- Support and existing users. Login, password reset, tutorial, documentation, unless you want to pay for your own support traffic.
- Education. What is, definition, how does it work, course, certification.
- Investors and press. Funding, valuation, revenue, crunchbase style research.
Our post on negative keywords covers building the list.
How to choose an agency for a SaaS business
- “What is our payback period?” If they cannot answer after seeing your numbers, they have not done the work.
- “What will we optimize toward?” Activation or paid, not trial signups.
- “We only get eight paid conversions a month. What now?” A good answer addresses the Smart Bidding threshold honestly.
- “What is your view on competitor and alternative terms?” They should raise the alternative cluster unprompted.
- “What would make you tell us to stop?” No answer means they are selling.
Our post on choosing a Google Ads agency covers contracts and management pricing covers fee models.
Common questions
How much should a SaaS company spend?
Enough to produce a decision, which usually means enough conversions for the bidding to learn. Underfunding a SaaS account is common and it guarantees an inconclusive test.
Why do our trials not convert?
Often because the account is optimizing toward trials, so it finds people who like trials. Switch the primary conversion to activation and the mix changes.
Should we bid on competitor names?
Yes if you have a real difference to lead with, and expect a low Quality Score and a high cost per click. “Alternative to” terms are usually better value.
Is Google Ads better than LinkedIn for B2B SaaS?
They do different jobs. Google reaches people actively looking. LinkedIn reaches people who fit the profile whether or not they are looking. Most programmes that work use both.
How long before it works?
Add your sales cycle to the ninety day learning window. For a product with a sixty day cycle, the first honest revenue read is around five months.
Where to go from here
Calculate your payback period before changing a single bid. Acquisition cost divided by monthly gross profit per account. If that number is above twelve months and your churn is not exceptionally low, no amount of campaign optimization will fix the economics.
Our Google Ads management page explains how we work, our case studies show the results, and you can get in touch for a straight read on your funnel.
