Adding Performance Max to Standard Shopping: When Two Campaigns Are Better Than One
Advertisers often grapple with whether to consolidate e-commerce ad spend into a single campaign type or deploy multiple campaigns to target different stages of the funnel. A recent experiment combining Standard Shopping and Performance Max (PMax) sheds light on how these campaigns can effectively co-exist, drive additional conversions, and yield better overall efficiency—if executed with careful planning.
Below, we dive into the process, insights, and tactical considerations uncovered during the test.
1. Background: One Product, Two Campaigns
In this scenario, an advertiser ran one Standard Shopping campaign and one Performance Max campaign, both featuring the same single product:
- Standard Shopping:
- Daily Budget: $2,600
- Target ROAS (tROAS): 100% (i.e., 1x)
- Already profitable but not fully utilizing daily budget
- Performance Max:
- Daily Budget: $500 (later scaled to $1,000)
- Running concurrently to capture incremental volume and cheaper conversions where possible
Key Question: How would layering PMax onto an existing, stable Standard Shopping campaign affect spend, cost, and returns?
2. Early Results: ROAS Redistribution & Surprising Spend Increase
2.1 PMax Takes the “Fast, Easy Wins”
Within a week of launching Performance Max, Standard Shopping’s ROAS dipped about 20% (e.g., from 90% to ~70–75%). Meanwhile, PMax reported a 200% ROAS:
- Why?
Performance Max “steals” the fastest, easiest conversions that Standard Shopping previously handled. The ultra-profitable, low-hanging fruit moves to PMax—driving its sky-high ROAS. In turn, the Standard Shopping campaign is left with an “average” level of conversion value, lowering its ROAS slightly.
2.2 Both Campaigns Spend More
A surprising outcome was that Standard Shopping spend actually increased by about 54%, despite the tROAS goal moving further away from 100%. Normally, if a campaign is performing below a tROAS goal, it spends less, not more. Yet, it scaled up, as did Performance Max.
Takeaway: Layering Performance Max did not cannibalize Standard Shopping’s volume in a zero-sum way. Instead, it unlocked additional spend for both campaigns, leading to an overall higher budget with more conversions.
3. The “Bolt-On” Effect: Why Running Both Helps
3.1 Standard Shopping Anchors High-Intent Clicks
By maintaining Standard Shopping as the primary driver for “inbound” searches (e.g., higher-intent queries), the campaign continues to capture predictable conversions at stable costs. Advertisers often use a tROAS or manual bidding approach here, focusing on:
- Product Listing Ads (PLAs) that appear for high-intent, e-commerce keywords.
- A consistent CPC range (e.g., around $3 per click).
- Strong historical performance with stable cost-per-acquisition (CPA) and return on ad spend (ROAS).
3.2 Performance Max for Broader & Cheaper Clicks
Performance Max is allowed to expand reach into:
- Display and YouTube: Tapping into cheaper cost-per-click (CPC) inventory (e.g., $0.80 clicks).
- Retargeting: It dynamically retargets users who abandoned carts or visited the site, boosting final-stage conversions.
- Additional PLA Slots: Google can run PMax-based Shopping ads, sometimes capturing searchers before Standard Shopping can.
Because PMax uses a conversion-focused smart bidding model, it often scoops up the “fast, easy conversions” that Standard Shopping might not fully maximize—especially if Standard Shopping is constrained by tROAS or daily budget settings.
4. Overall Outcomes: More Revenue & Better Efficiency
4.1 Improved Global Metrics
In the advertiser’s data snapshot:
- Global ROAS (across both campaigns) increased by about 20%.
- Conversion Value rose 127%.
- Total Spend increased 90%, yet still at improved efficiency.
PMax’s lower CPCs (mainly from Display/YouTube placements) helped reduce the blended cost per click across all campaigns. Meanwhile, Standard Shopping continued capturing high-intent searches.
4.2 Tailoring the “Bolt-On” Budget
Performance Max started at $500/day and eventually increased to $1,000/day. Because PMax identified easy, profitable wins, scaling up the daily budget didn’t significantly hurt either campaign’s efficiency. Standard Shopping continued to spend closer to $2,600/day, generating the bulk of stable conversions while PMax added incremental volume.
Note: The advertiser warns against giving Performance Max too much budget right away; otherwise, it might overshadow Standard Shopping and yield greater volatility.
5. Tips for Combining PMax with Standard Shopping
- Start Small with PMax
Allocate a modest daily budget (e.g., ~10–20% of what Standard Shopping spends). Observe whether PMax truly captures new, cheaper clicks—or if it simply shifts conversions from existing campaigns. - Watch Overall ROAS, Not Just Channel ROAS
If Standard Shopping sees a drop in ROAS but your overall combined ROAS (and revenue) rises, that’s usually a positive sign. - Don’t Panic if Standard Shopping’s ROAS Dips
PMax is likely stealing the best conversions. This rebalancing can still yield higher overall profit and more total sales. - Allow Time for Smart Bidding to Adjust
It’s normal for campaigns to fluctuate as Google’s machine learning identifies new audiences. Give it at least 1–2 weeks to see a stable trend. - Use Target ROAS (tROAS) with Caution
In Standard Shopping, tROAS can help maintain a baseline, but it may also prevent volume growth. Low tROAS settings (50–60%) can encourage more spend if you’re aiming for incremental scale.
6. Final Thoughts
Running Performance Max and Standard Shopping together can deliver a powerful, complementary strategy. Standard Shopping typically owns core, inbound e-commerce searches; PMax extends your reach across multiple networks—often at lower CPCs—and helps recapture lost leads via remarketing. While each campaign’s individual metrics may shift, the key is overall performance: higher total revenue, stronger blended ROAS, and better coverage of the funnel.
It’s not a one-size-fits-all approach—campaign structures and bidding tactics need continuous monitoring. But for advertisers looking to expand beyond the typical Standard Shopping environment, adding a well-managed PMax campaign can create synergy, unlocking new reach and giving old campaigns fresh opportunities for scale.