B2B Google Ads
Bidding Strategy:
tCPA vs tROAS
vs Manual

Manual CPC puts you in direct control of how much you bid on each keyword. You set the max CPC; Google charges up to that amount. No algorithm, no learning period, no minimum conversion volume required.

In B2B, Manual CPC is the correct default for any campaign that is new, recently restructured, or running below 20 conversions per month. The smart bidding algorithms require data to function — running tCPA on a campaign with 8 conversions a month is like asking someone to learn a pattern from six data points. The result is usually severe impression share restriction or erratic bidding that produces unpredictable CPL swings.

When Manual CPC is the right choice:

• New campaigns with zero conversion history
• Post-restructure: new ad groups, new campaigns, new keywords that have no data yet
• Campaigns with fewer than 20 conversions per month
• When you need maximum impression share and want to prioritise data gathering over CPL efficiency
• Brand campaigns — CPCs are already low, competition is minimal, smart bidding adds no value

Common mistake: leaving Manual CPC in place after the account has accumulated enough conversion volume for smart bidding to work. Once you hit 30+ conversions per campaign per month, Manual CPC typically underperforms Maximise Conversions — because the algorithm can find better auctions than manual bid logic can predict.

Maximise Conversions tells Google to get as many conversions as possible within your daily budget — without a CPL target. It’s smart bidding, but unconstrained. The algorithm spends your entire budget optimising for conversion volume, not efficiency.

In the B2B bid strategy progression, Maximise Conversions is the bridge: you switch here from Manual CPC once you have 30 conversions per campaign per month, and you stay here until you have enough data to set a meaningful tCPA target.

When Maximise Conversions is the right choice:

• 30–50 conversions per campaign per month — enough for the algorithm to work, not enough for a reliable tCPA
• When you want to let the algorithm learn without a target constraining it prematurely
• When you’re entering a new market or testing new keywords and need volume data quickly
• After a major restructure — use it for 3–4 weeks to re-seed conversion data before switching to tCPA

The risk in B2B: without a tCPA cap, Maximise Conversions can spend your entire budget in the first few hours of the day at high CPCs, leaving no budget for later in the day when B2B decision-makers are typically more active. Monitor hourly spend distribution and set a sensible daily budget ceiling.

Target CPA is the workhorse bid strategy for mature B2B accounts. You tell Google your target cost-per-acquisition; it adjusts bids in every auction to get conversions at or near that target. Unlike Maximise Conversions, it’s designed for efficiency rather than volume.

When it works well — which requires the data thresholds below — tCPA can sustainably reduce CPL while maintaining or growing conversion volume. It compounds: lower CPL means the same budget buys more leads, which means more data for the algorithm, which means it improves further.

Requirements for tCPA to work in B2B:

• Minimum 50 conversions per campaign per month (Google’s official minimum is 30 — in B2B, treat 50 as the real threshold)
• Conversion tracking must be counting the right event — see the CPL audit guide for what to check
• Your target must be set at least 20–30% above your current average CPL on switchover day — setting it at your ideal CPL immediately is the most common mistake
• Budget of at least 10× your target CPA as a daily budget (e.g., if tCPA = €200, daily budget ≥ €2,000) — otherwise the algorithm can’t generate enough auctions to optimise

If you want an expert to diagnose why your tCPA campaigns aren’t hitting target rather than working through this alone, here’s how I work with B2B companies — I do this kind of bid strategy audit as part of every account review.

Target ROAS tells Google to optimise for conversion value, not conversion volume. Instead of a cost target, you set a revenue return target: e.g., 400% tROAS means you want €4 back for every €1 spent. The algorithm bids more aggressively when it predicts a high-value conversion and less when it predicts a low-value one.

In ecommerce, tROAS is the natural evolution of tCPA — because every purchase has a revenue value attached. In B2B, the picture is murkier, and tROAS underperforms in most accounts I audit.

Why tROAS struggles in B2B:

• No real-time revenue data: most B2B companies don’t pass deal value back to Google Ads at conversion time. Without this, tROAS assigns an arbitrary or equal value to every lead — which makes it identical to tCPA but with an extra layer of complexity.
• Long sales cycles: tROAS needs to know the outcome of each conversion quickly to adjust bids. If your average sales cycle is 60–90 days, Google is bidding on signals it won’t receive for months.
• Low conversion volume: tROAS requires even more conversion data than tCPA. Google recommends 50 conversions per month; in practice, for tROAS to work well in B2B you need 100+.

When tROAS does work in B2B: if you have offline conversion import set up — passing closed-won deal values from your CRM back to Google Ads via the Offline Conversions API — then tROAS becomes genuinely powerful. It allows the algorithm to distinguish between a €5,000 deal and a €50,000 deal and bid accordingly. This is advanced infrastructure, but it’s the right long-term direction for any B2B account spending €20k+/month.