How ROAS actually works
ROAS is a channel-level ratio. You take the revenue Google Ads (or Meta, or Amazon) claims it drove and divide by what you spent. Sounds simple. The traps are in the numerator. Platform-reported revenue includes attribution-modelled sales, view-through conversions, and often double-counts against other channels. A ROAS of 4.0 on the Google Ads dashboard can be a real ROAS of 2.4 once you strip out sales that would have happened anyway.
Healthy ROAS depends on your margin
There is no universal healthy ROAS. A 3.0 ROAS is profitable at 40 percent gross margin and loss-making at 20 percent gross margin. The break-even calculation is simple: break-even ROAS equals 100 divided by your margin percent. At 25 percent margin, break-even is 4.0. Anything above 4.0 makes contribution profit. Anything below is losing money before you count overhead.
ROAS vs MER (blended metric)
ROAS is channel-specific. MER (marketing efficiency ratio) is your entire revenue divided by your entire marketing spend, across every channel. A brand can have a great Google Ads ROAS and a terrible MER if the two channels are canniballing each other or if unattributed revenue is being over-credited. On accounts spending $100K+ a month, iClick optimises to MER first and channel ROAS second.
Common ROAS mistakes
The three most expensive ROAS mistakes we see: (1) using platform-reported ROAS without validating against Shopify or GA4; (2) setting a fixed target ROAS across every SKU when margin varies from 15 to 60 percent; (3) chasing a high ROAS by pulling budget from prospecting, which starves the top of the funnel and slowly kills the account over 60 to 90 days.
