Search vs. Performance Max: a budget allocation framework
The split we settled on after a year of A/B testing across bridging finance accounts.
Through 2023 we ran a series of structured tests across bridging accounts to find the right budget split between manual Search and Performance Max. By February 2024 the framework had stabilised. The numbers below are the split we settled on as a default, and the cases where we deviated from it.
The default split
60% manual Search on tightly themed commercial-intent ad groups, 30% Performance Max with brand exclusions and proper asset-group discipline, 10% YouTube as a mid-funnel layer feeding both.
This split outperformed both Search-heavy (90/10) and PMax-heavy (30/60) structures on cost per booked call over the 12-month test period. The 30% PMax allocation captured the brand-adjacent harvesting upside without giving the algorithm enough budget to wander into unprofitable audiences.
When to push more into PMax
Established brand with real search volume on the broker's name - PMax becomes much more efficient because it has clean brand signal to harvest from. We pushed this allocation as high as 45% on accounts with strong brand recognition.
Conversely, new brands with no search volume on their own name should run minimal PMax - the algorithm has no efficient starting point and tends to waste budget exploring.
When to push more into Search
Specialist scheme types - auction bridging, part-built development finance, refurb-to-refinance - where the long-tail commercial intent terms were both meaningful and under-served by PMax. We have gone as high as 75% manual Search on accounts heavily specialised in one scheme type.
PMax struggles to find specialist long-tail intent reliably. Manual Search wins on niche.
The 60/30/10 default held through most of 2024. The split shifted slightly in favour of PMax through Q4 as Google's ML kept improving, but the underlying logic - manual Search for niche commercial intent, PMax for brand-adjacent harvesting, YouTube as mid-funnel - remained the right structure for bridging accounts at our typical budget levels.
Capital Edge publishes one note a month on UK bridging finance, paid acquisition, and AI-led outbound. Written for brokers, by the team running the playbook.