Facebook Ads Cost Per Purchase Benchmarks for Marketplaces in United States

Key takeaways

• This analysis looks at cost-per-purchase trends for industry Marketplaces and target country United States compared to the global trend, based on $3B worth of advertising data from our dataset, which provides strong directional benchmarks.
• United States Marketplaces ran above market on average: $62.84 vs a global baseline of $47.82 (+31% higher).
• Volatility in the selected data was very high (average month-to-month swing of about $50) compared to the steady global baseline (~$3.25).
• Seasonal patterns show a December lift and elevated costs into January–February in both series; the selected data also shows an additional late-summer spike and a sharp September trough.

What the selected data shows

• Average: $62.84 cost-per-purchase across the period.
• High/low: Peak in August at $170.03; low in September at $5.48 (range of $164.55).
• Start-to-end trend: From $34.33 in October to $5.48 in September, an 84% decrease across the window.
• Volatility: Average absolute month-to-month change of $49.98, with multiple extreme swings.
• Notable spikes/dips:
• November dipped 47% vs October.
• December rebounded to $39.78.
• January–February surged to $72.05 and $139.25 respectively.
• March corrected sharply to $49.24 (−65% vs February).
• August spiked to $170.03 (+250% vs July).
• September fell to the series low (−97% vs August).

Comparison to the global baseline

• Baseline average: $47.82; high $53.89 (February), low $32.29 (September), range $21.60.
• Baseline trend: From $46.67 in October to $32.29 in September (−31% across the period), with a modest December–February lift and gradual softening into late Q3.
• Relative positioning:
• The selected series was above market in 7 of 12 months (notably January–August except March).
• Key over-market months: February ($139.25 vs $53.89 baseline) and August ($170.03 vs $45.69).
• Under-market months: October, November, December, March, and September.
• Volatility contrast: Selected data is markedly more erratic than the baseline (roughly 15× higher average monthly swing).

Seasonality and pattern read

• Both datasets show a Q4-to-Q1 uplift: December is higher than November, and levels remain elevated through January–February.
• The selected United States Marketplaces data adds a pronounced late-summer spike in August and an exceptional drop in September, while the baseline shows a smoother descent into September.

Bottom line for marketers

United States Marketplaces cost-per-purchase benchmarks were, on average, above the global baseline and substantially more volatile, with significant spikes in February and August and a pronounced drop in September. The global trend remained steadier, peaking modestly in winter and easing into late Q3. Understanding cost-per-purchase benchmarks on Facebook Ads in industry Marketplaces and United States helps advertisers make more efficient budget and creative choices.