Attribution Windows Explained: 1-Day vs 7-Day Click

Your Meta Ads dashboard shows 150 conversions this week. Your Shopify backend shows 200 orders. Before you accuse Meta of lying, check your attribution window. If you're using 1-day view, 1-day click attribution, you're only counting conversions that happened within 24 hours of an ad interaction. Switch to 7-day click and that number might triple—but neither figure is wrong. They measure different things.

Attribution windows determine which conversions Meta counts as ad-driven. Understanding how they work isn't just academic—it affects how you evaluate campaign performance, optimize delivery, and allocate budget. This guide breaks down every attribution window option, when to use each, and how window choice impacts your reported numbers.

What Are Attribution Windows?

An attribution window is the time period after an ad interaction during which a conversion gets credited to that ad. If someone clicks your ad today and purchases within the window, Meta attributes the sale to the ad. If they purchase after the window closes, the conversion isn't attributed—even if the ad clearly influenced the decision.

Meta offers multiple window options:

• 1-day click: Conversions within 24 hours of clicking an ad
• 7-day click: Conversions within 7 days of clicking an ad
• 1-day view: Conversions within 24 hours of viewing an ad (without clicking)
• 7-day click, 1-day view (default): Combines 7-day click and 1-day view
• 28-day click: Available for some campaigns, especially app installs

How Each Attribution Window Works

1-Day Click Attribution

Counts only conversions where the user clicked an ad and converted within 24 hours. This is the strictest window—if they wait until day 2 to purchase, it doesn't count.

Best for: Impulse purchases, flash sales, low-consideration products, performance marketers who want conservative attribution.

Drawback: Dramatically undercounts for products with longer consideration cycles.

7-Day Click Attribution

Counts conversions where the user clicked and converted within 7 days. Most purchases happen within this window, making it the standard for e-commerce.

Best for: Most e-commerce, lead generation with short sales cycles, standard conversion optimization.

Drawback: May still undercount high-consideration purchases (B2B, luxury goods).

1-Day View Attribution

Counts conversions within 24 hours of viewing an ad—even if the user never clicked. This captures "view- through" conversions where the ad influenced awareness but didn't generate a direct click.

Best for: Awareness campaigns, video ads, brand recognition measurement.

Drawback: Can overattribute—user might have purchased anyway regardless of seeing the ad.

7-Day Click + 1-Day View (Default)

Meta's default setting combines 7-day click and 1-day view. If someone clicks within 7 days OR views within 1 day before converting, the ad gets credit.

Best for: General-purpose campaigns, balanced attribution, most advertisers.

Drawback: Can inflate numbers compared to click-only attribution.

Why Attribution Windows Matter for Optimization

Attribution settings don't just affect reporting—they determine what data Meta's algorithm uses to optimize delivery. When you set a 7-day click window, the algorithm optimizes to find users likely to convert within 7 days. With 1-day click, it optimizes for immediate converters.

Algorithm Learning

Longer windows give the algorithm more conversion data to learn from. If your true conversion cycle is 5 days but you use 1-day click, the algorithm only sees 20% of your conversions—it's learning from incomplete data.

Audience Selection

Different windows target different user behaviors. 1-day click attracts impulse buyers. 7-day click reaches researchers who compare before buying. Your window choice influences who sees your ads.

Bid Calibration

Meta's bidding system calibrates based on attributed conversions. If you're using 1-day click but your average customer takes 4 days to purchase, Meta thinks your conversion rate is lower than reality and may underbid for valuable users.

Comparing Attribution Windows: The Numbers

Here's how the same campaign might report under different windows:

Same spend, same actual conversions—but reported performance varies by 3x depending on attribution. This is why comparing campaigns with different attribution settings is misleading.

Choosing the Right Attribution Window

Match Your Sales Cycle

Analyze your customer journey. How long between first site visit and purchase? If 80% of customers convert within 3 days, 7-day click captures the vast majority. If your sales cycle is 30 days, even 7-day click misses significant conversions.

Consider Product Type

Align with Business Goals

Conservative attribution (1-day click) is useful when:

• You need to justify spend to skeptical stakeholders
• You want to measure only high-intent conversions
• You're comparing Meta to other channels with short windows

Liberal attribution (7-day click + view) is appropriate when:

• You trust that ad exposure influences purchases
• You want maximum data for algorithm optimization
• Your product has a multi-day consideration cycle

How to Change Attribution Windows

Ad Set Level (Standard)

When creating or editing an ad set, scroll to the "Optimization & Delivery" section. Under "Attribution Setting," select your preferred window. Changes apply to future conversions—historical data uses the original setting.

Reporting Level (Compare After the Fact)

In Ads Manager reporting, you can compare different attribution windows without changing campaign settings. Go to Columns → Compare Attribution Settings. This shows how your existing data would look under different windows—useful for analysis without affecting optimization.

View-Through Attribution: When to Include It

View-through attribution counts conversions from users who saw (but didn't click) your ad. It's controversial—skeptics argue these users might have converted anyway.

Arguments for Including View-Through

• Captures brand awareness impact that doesn't manifest as clicks
• Video ads often influence without generating clicks
• Mobile users frequently see ads and purchase later on desktop
• Gives algorithm more data for optimization

Arguments Against View-Through

• Risk of claiming credit for organic conversions
• Can inflate metrics and mask true performance
• Harder to defend to stakeholders who question causation
• May lead to overinvestment in low-performing campaigns

Recommendation

Use 1-day view (not longer) as a reasonable middle ground. It captures legitimate view-influence while limiting overcounting. If someone saw your ad Monday and purchased Friday without ever clicking, the ad's contribution is questionable.

Post-iOS 14 Attribution Changes

iOS 14.5 and App Tracking Transparency significantly impacted attribution:

Modeled Conversions

Meta now uses statistical modeling to estimate conversions from iOS users who opted out of tracking. These modeled conversions are included in your totals but aren't verified at the user level.

Delayed Reporting

iOS conversions may appear 24-72 hours later as Meta's modeling updates. Don't make optimization decisions based on same-day data—wait 3+ days for stabilization.

SKAdNetwork Limitations

Apple's SKAdNetwork provides aggregated, delayed conversion data with limited attribution windows. This affects app install campaigns more than web conversion campaigns.

Attribution Window Best Practices

Be Consistent

Use the same attribution window across all campaigns you want to compare. If Campaign A uses 7-day click and Campaign B uses 1-day click, their CPA comparison is meaningless.

Document Your Settings

Record what attribution window each campaign uses. When reviewing historical performance or handing off to new team members, this context is essential.

Match to Reporting

If you report ROAS to leadership using 7-day click + 1-day view, ensure your optimization uses the same window. Optimizing on one window while reporting on another creates disconnects.

Test Different Windows

Run parallel campaigns with different attribution windows to see how they perform. You might find that 1-day click optimization actually produces more conversions because it focuses the algorithm on high-intent users.

Cross-Reference with Backend

Always compare Meta-reported conversions to your source of truth (Shopify, GA4, CRM). If Meta shows 100 conversions on 7-day click + 1-day view and your backend shows 95 purchases, attribution is reasonably accurate. If the gap is 40%, you have tracking issues beyond attribution windows.

Attribution Windows and Multi-Touch Reality

Attribution windows assume "last touch" credit—the ad interaction closest to conversion gets all the credit. In reality, customers often see multiple ads across days or weeks before purchasing.

The Problem

User sees Ad A (video) Monday, clicks Ad B (carousel) Wednesday, views Ad C (retargeting) Friday, then purchases Saturday. Under 7-day click + 1-day view, Ad B gets full credit. Ad A's awareness contribution is invisible.

The Solution

Use Meta's attribution reports (under Business Suite → Attribution) to see multi-touch paths. This shows how different ads contribute to conversion journeys, not just who gets final credit.

Key Takeaways

• Attribution windows determine which conversions Meta credits to your ads
• 7-day click + 1-day view (default) captures most conversions but may overcount
• 1-day click is conservative but misses longer consideration cycles
• Your window choice affects both reporting AND algorithm optimization
• Match attribution window to your actual sales cycle for accuracy
• Be consistent—comparing campaigns with different windows is misleading
• Post-iOS 14, expect modeled conversions and reporting delays

FAQ

Should I use the same attribution window for all campaigns?

Yes, if you want to compare them meaningfully. The exception: different campaigns with genuinely different goals (brand awareness vs. direct response) might warrant different windows, but document the rationale.

Why does Meta default to 7-day click + 1-day view?

It captures the most conversions, which makes reported ROAS higher. Higher ROAS encourages more spending. It's also genuinely useful for algorithm optimization—more conversion data means better learning.

Can I change attribution windows retroactively?

You can view historical data under different windows in reporting, but you can't change what window was used for optimization. A campaign optimized on 1-day click can't retroactively benefit from 7-day click learning.

How do I explain attribution windows to stakeholders?

Frame it as "how long after seeing/clicking an ad do we give credit for a sale?" Use a concrete example: "If someone clicks our ad Monday and buys Friday, do we count that? With 7-day click, yes. With 1-day click, no."

What if my true sales cycle is longer than 7 days?

You'll undercount Meta's contribution. Use 7-day click (the longest available for most campaigns) and understand it's a floor, not the ceiling. Supplement with lift studies or incrementality tests to measure true impact.