Performance Max for SaaS: Why It's Eating Your Budget (And How to Fix It)

Performance Max is the campaign type Google wants you to use. It's also the one that wastes the most budget in every SaaS account we audit.

The concept is simple: you give it a budget and some creative assets, and Google runs your ads everywhere (Search, Display, YouTube, Gmail, Maps, Discover). The algorithm decides everything.

For e-commerce with thousands of SKUs and clean conversion tracking, PMax can be a monster. For B2B SaaS with a 45-day sales cycle and three decision-makers? It's usually a cash-burning machine.

Here's how to tell if your PMax is a problem, and what to do about it.

The PMax black box problem for SaaS

PMax runs on conversion signals. The more conversions you feed it, the better it optimizes. An e-commerce store gets hundreds of purchases a day. A B2B SaaS might get 15 demo requests a month. That's not enough data for the algorithm to learn anything useful.

The result: PMax goes looking for volume wherever it's cheapest, Display and YouTube, and brings back impressions that don't convert. Your budget drains. Your "conversions" are Display visitors who bounced after three seconds.

How to audit your PMax campaigns

First thing to check: the placement report. In Google Ads, go to Insights → Placements. Look at the breakdown: how much is going to Search vs Display vs YouTube vs Discover.

If Search represents less than 30% of your spend, your PMax is essentially disguised Display.

Next, check the search terms. Google added search term transparency to PMax in late 2025. Look at the queries: are they high-intent ("project management software for teams") or informational ("what is project management")? If it's the latter, your PMax is cannibalizing your Search budget.

When to fix vs when to kill PMax

Keep PMax if: you have 50+ conversions per month, your offline conversion tracking is in place, and you have precise audience signals (customer match lists, in-market audiences for your ICP).

Fix PMax if: you have the conversion volume but the placement mix is wrong. Add negative keywords (you now get 10,000 per campaign), tighten your audience signals, and exclude underperforming Display and YouTube placements.

Kill PMax if: you have fewer than 30 conversions per month, no offline conversion data, and your placement report shows 60%+ going to Display. Reallocate to standard Search campaigns where you control everything.

The SaaS-specific PMax setup that actually works

If you want to keep PMax running, here's the minimum viable setup.

Conversion action: offline conversion (SQL or Opportunity), not form fill.

Audience signals: upload your customer match list (existing customer emails), add in-market audiences that match your ICP, add custom intent audiences built from your competitors' URLs.

Asset groups: one asset group per product or use case. Not one catch-all group.

Negatives: add a list of 200+ negative keywords before you launch.

Budget: start at 20–30% of your total budget, no more. Search keeps the majority. Monitor placements every week for the first month.

What to do with the recovered budget

When you cut or scale back PMax, you free up 30–50% of your budget. Don't let it sit idle.

Reinvest in: exact match Search campaigns on your highest-intent keywords, competitor campaigns (people searching for your competitors are active buyers), and Search remarketing (RLSA) targeting people who've already visited your site.

These three channels deliver a CAC 2–3× lower than a poorly configured PMax.

The bottom line

PMax isn't inherently bad. It's a powerful tool that's misused in 90% of SaaS accounts. The problem is that Google pushes it as the default, and most agencies activate it without the prerequisites in place.

If you don't have the conversion volume and CRM tracking to feed it properly, PMax is costing you money. Audit it, fix it, or cut it. Your CAC will thank you.