Reach & Frequency
Part of Media budgets and allocation
Comparing channel costs on a consistent outcome
Compare channel costs using one outcome definition, a clear assignment rule and the same cost boundary.
Compare channels on the same business outcome, observation period and stated cost boundary. A cheap click or supplier-reported conversion is not necessarily a cheap accepted enquiry or sale.
First establish whether outcomes can be assigned to channels under a defensible rule. A whole-campaign total alone cannot supply a separate denominator for each one.
Define and assign the outcome
For enquiries, specify acceptance, duplicate handling, eligible locations and the response period. For sales, decide whether the unit is an order, a paid order or another business record.
Use the same rule for every channel being compared. Show outcomes that cannot be assigned as unattributed rather than distributing them by guesswork.
Keep supplier-reported actions in separate columns with their settings. Check the platform’s conversion-counting settings when interpreting reported counts.
Google Ads reporting has settings for primary and secondary conversion actions and conversion windows. Record the settings used. These platform reports are not the business’s unique outcome count.
State which costs are included
Media-only cost per outcome is media cost divided by outcomes assigned under the agreed rule. A broader directly attributable cost includes channel-specific creative, services or technology as well as media.
Apply the same inclusion rule to each channel. Show shared costs separately if allocating them to channels would be arbitrary.
Reconcile the period and quoted GST basis before comparing figures.
Suppose, solely to show the arithmetic, Channel A costs A$3,000 in media and has 12 accepted enquiries assigned to it. Channel B costs A$1,200 in media and has six accepted enquiries under the same rule and period.
Their media-only costs are A$250 and A$200 per accepted enquiry. If B also requires a dedicated A$600 asset, its directly attributable cost is A$1,800, or A$300 per accepted enquiry.
These invented figures are not evidence about either channel’s performance.
Check / Record before comparing
- Outcome
- Qualification, duplicates, cancellations and assignment rule
- Period
- Spend dates and allowed response time
- Market
- Eligible locations and products
- Cost
- Media, fees and directly attributable work included
- Reporting
- Business outcomes, unattributed outcomes and supplier-credited actions separately
Key Checks Before Comparing Channel Costs
- Outcome qualification ruleDefined for all channels, including duplicates and cancellations
- Response periodConsistent across channels, with clear start and end dates
- Eligible marketSpecified locations and products applied uniformly
- Cost inclusion ruleMedia, fees and directly attributable work clearly defined
- Reporting separationBusiness outcomes, unattributed and supplier-credited actions kept separate
Use the rate for the decision it can support
Show spend and raw outcome counts beside the rate, especially when counts are small. An observed average does not predict what the next dollar will produce.
Supplier-attributed actions can overlap across systems. An assigned outcome does not prove that a channel caused an additional sale. Do not add supplier conversion totals and call them unique customers.
If assignment is too incomplete for a useful channel rate, report the comparable media and response measures separately. Use the shared business total for the whole campaign.
A channel with an awareness job should be assessed against its agreed awareness evidence rather than forced into a short-term sales denominator.
Treat a cost difference as a reason to investigate or adjust the allocation, with its measurement limits visible.
