How should you split an advertising budget across channels?

"Let's split the budget evenly between Meta and Google" is the most expensive decision in most accounts. Channels do not do the same job; budget should be allocated by stage of the buying journey, not by channel.

Three stages, three different jobs

• Capturing demand: The customer is already looking. Google search and marketplace ads work here. Cost per conversion is lowest, but volume is capped by the size of existing demand.
• Creating demand: Building interest when nobody is searching. Meta, TikTok and YouTube sit here. It looks expensive, but it is also what grows search volume.
• Remarketing: Bringing back an audience that already knows you. Delivers the highest return on a small budget, which is why it is the first campaign to set up.

Find the saturation point

Demand-capture channels have a saturation point: once search volume runs out, raising the budget increases cost per click without increasing conversions. If the account's impression share is above 80 percent, that channel is saturated and any extra budget should go to demand creation.

Raising budget without measuring this produces the familiar picture in most accounts: spend went up, sales stayed flat.

Ring-fence a test budget

Set aside 10–15 percent of the total budget for testing new channels and new creative. That money shows as a loss in the short term; in return you find next quarter's winner. Accounts without a test budget cannot grow once the current channel saturates.

Creative matters more than targeting

With the same budget, changing the creative usually makes a bigger difference than changing the targeting. Before discussing budget allocation, make sure you have at least three different creatives per channel — otherwise you are not measuring which channel fails, but which visual does.