How to Track Affiliate Conversions with Stripe

Stripe powers payments for millions of SaaS businesses, but it doesn't include native affiliate tracking. You need additional tools to connect affiliate referrals to Stripe conversions.

This guide explains how affiliate tracking works with Stripe, your options for implementation, and best practices for accurate attribution.

How Stripe Affiliate Tracking Works

The Basic Flow

1. Visitor clicks affiliate link → Tracking cookie stored in browser
2. Visitor browses your site → Cookie persists
3. Visitor signs up → Customer created (may or may not involve payment yet)
4. Visitor pays via Stripe → Payment successful
5. Attribution happens → System connects payment to original affiliate click
6. Commission calculated → Affiliate credited for the conversion

The technical challenge: connecting step 1 (click) to step 4 (Stripe payment) when they might be days or weeks apart.

What Needs to Connect

Affiliate tracking system must know:

• Which affiliate link was clicked
• When it was clicked
• The visitor's identity (usually a cookie)

Stripe must know:

• Customer identity
• Payment details
• Subscription status

Your system must bridge these:

• Connect visitor (cookie) to customer (email/ID)
• Pass customer identity to affiliate system
• Track ongoing payments for recurring commissions

Implementation Options

Option 1: Purpose-Built Affiliate Software (Recommended)

Platforms like PromoteKit, Rewardful, or FirstPromoter handle the entire integration:

How it works:

1. Add a tracking script to your site
2. Connect your Stripe account via OAuth
3. The platform handles attribution automatically

Advantages:

• Minimal development required
• Handles edge cases (trials, upgrades, refunds)
• Webhook management included
• Dashboard and reporting built-in
• Recurring commission tracking automatic

Best for: Most SaaS businesses. Unless you have unique requirements, purpose-built software is the right choice.

Option 2: Affiliate Networks

Platforms like ShareASale, CJ Affiliate, or Impact use postback/pixel tracking:

How it works:

1. Add network's tracking pixel to your site
2. Fire a conversion pixel when payment occurs
3. Pass order details (amount, order ID) to the network

Advantages:

• Access to network's affiliate base
• Established trust among affiliates

Disadvantages:

• Designed for e-commerce, not SaaS subscriptions
• Recurring commission tracking often manual
• Higher fees
• Less control

Best for: Companies wanting access to established affiliate networks, primarily selling one-time products.

Option 3: Build In-House

Create your own tracking system:

Required components:

• Tracking script to drop and read cookies
• Database to store click data
• Stripe webhook handlers for payments
• Attribution logic to connect clicks to payments
• Affiliate dashboard
• Payout management system

Advantages:

• Complete control
• No ongoing software costs
• Customization for unique needs

Disadvantages:

• Significant development time (weeks to months)
• Ongoing maintenance burden
• Edge cases are complex
• Opportunity cost vs. core product

Best for: Very large programs with unique requirements or engineering capacity to spare.

Technical Implementation Details

Tracking Script

The tracking script runs on your marketing site and handles:

Cookie setting:

// Simplified example
function setAffiliateCookie(affiliateId) {
  document.cookie = `affiliate=${affiliateId}; max-age=7776000; path=/`;
  // 90-day cookie (7776000 seconds)
}

// Parse referral from URL
const urlParams = new URLSearchParams(window.location.search);
const affiliateId = urlParams.get('ref');
if (affiliateId) {
  setAffiliateCookie(affiliateId);
}

Key considerations:

• Use first-party cookies (set on your domain)
• Set appropriate duration (30-90 days typical)
• Handle multiple affiliate touches (first-click vs. last-click)

Connecting Visitor to Customer

When a visitor becomes a customer, connect their cookie to their account:

At signup:

// Read affiliate cookie
function getAffiliateCookie() {
  const match = document.cookie.match(/affiliate=([^;]+)/);
  return match ? match[1] : null;
}

// Include in signup request
const affiliateId = getAffiliateCookie();
if (affiliateId) {
  // Pass to your backend with signup data
  signupData.referredBy = affiliateId;
}

In your backend:

// When creating Stripe customer
const customer = await stripe.customers.create({
  email: user.email,
  metadata: {
    affiliate_id: user.referredBy || '',
    signup_date: new Date().toISOString()
  }
});

Storing the affiliate ID in Stripe customer metadata allows attribution when payments occur.

Stripe Webhooks

Listen for Stripe events to track conversions:

Essential events:

• checkout.session.completed — New purchase
• invoice.paid — Subscription payment
• customer.subscription.created — New subscription
• customer.subscription.updated — Plan changes
• customer.subscription.deleted — Cancellation
• charge.refunded — Refund (reverse commission)

Webhook handler example:

app.post('/webhooks/stripe', async (req, res) => {
  const event = stripe.webhooks.constructEvent(
    req.body,
    req.headers['stripe-signature'],
    webhookSecret
  );

  switch (event.type) {
    case 'invoice.paid':
      const invoice = event.data.object;
      const customer = await stripe.customers.retrieve(invoice.customer);
      const affiliateId = customer.metadata.affiliate_id;

      if (affiliateId) {
        await recordCommission({
          affiliateId,
          amount: invoice.amount_paid,
          invoiceId: invoice.id,
          customerId: customer.id
        });
      }
      break;

    case 'charge.refunded':
      // Reverse commission
      break;
  }

  res.json({ received: true });
});

Handling Subscription Lifecycle

SaaS subscriptions have complex lifecycles. Your tracking must handle:

Trials:

• Customer signs up (affiliate ID captured)
• Trial period (no payment yet)
• Trial converts (first payment → commission)
• Trial expires (no commission)

Upgrades/Downgrades:

• Customer upgrades plan → Increased commission
• Customer downgrades → Decreased commission
• Handle prorations correctly

Cancellations:

• Subscription canceled → Stop future commissions
• Customer reactivates → Resume commissions (same affiliate?)

Refunds:

• Full refund → Reverse commission
• Partial refund → Partial reversal
• Chargeback → Reverse commission

This complexity is why purpose-built software is valuable—these edge cases take significant time to handle correctly.

Attribution Models

Last-Click Attribution (Standard)

The last affiliate link clicked before conversion gets credit.

Pros:

• Simple to implement
• Clear, unambiguous
• Industry standard

Cons:

• May not credit affiliate who introduced customer
• Can be gamed with late-stage cookie stuffing

First-Click Attribution

The first affiliate link clicked gets credit, regardless of later clicks.

Pros:

• Credits discovery
• Rewards content that introduces customers

Cons:

• Doesn't credit later influence
• Old cookies may attribute unrelated conversions

Time-Based Weighting

Recent clicks weighted more heavily than older clicks.

Pros:

• Balances recency and introduction
• More nuanced attribution

Cons:

• Complex to implement
• Harder to explain to affiliates

Recommendation

Start with last-click attribution. It's simple, understood, and works well enough for most programs. Consider more complex models only if you have clear evidence they'd be more accurate.

Best Practices

Use First-Party Cookies

Third-party cookies are being phased out. Set cookies on your own domain:

Good: cookie set on yourdomain.com Problematic: cookie set on affiliatetracker.com

Store Affiliate ID in Stripe Metadata

Always store the affiliate ID on the Stripe customer:

await stripe.customers.create({
  email: email,
  metadata: {
    affiliate_id: affiliateId,
    referred_at: new Date().toISOString()
  }
});

This creates a persistent record that survives cookie clearing.

Handle Missing Attribution Gracefully

Not every customer will have affiliate attribution. Don't break your flow:

const affiliateId = customer.metadata?.affiliate_id;
if (affiliateId) {
  await processCommission(affiliateId, payment);
}
// Continue regardless

Test Thoroughly

Before launch, verify:

• Clicks are tracked correctly
• Cookies persist appropriately
• Customer creation captures affiliate ID
• Payments trigger commission recording
• Refunds reverse commissions
• Cancellations stop future commissions
• Upgrades/downgrades handled correctly

Monitor for Issues

After launch, watch for:

• Missing attributions (affiliate complaints)
• Duplicate attributions
• Webhook failures
• Cookie problems

Set up alerts for anomalies.

Common Integration Issues

Cookie Blocked or Cleared

Problem: Visitor clicks affiliate link but cookie is blocked (Safari ITP, privacy extensions) or cleared before conversion.

Solutions:

• Use first-party cookies
• Offer coupon codes as backup attribution
• Store click data server-side with visitor fingerprint (limited reliability)

Long Conversion Cycles

Problem: Customer converts after cookie expires.

Solutions:

• Extend cookie duration (90-180 days)
• Capture email early and attribute later
• Accept some unattributed conversions

Multiple Devices

Problem: Customer clicks on mobile, purchases on desktop.

Solutions:

• Account-based tracking (link affiliate to account, not just cookie)
• Coupon codes
• Accept some cross-device attribution loss

Webhook Reliability

Problem: Stripe webhooks occasionally fail or arrive out of order.

Solutions:

• Implement idempotency (don't double-count)
• Retry logic with exponential backoff
• Reconciliation jobs to catch missed events

Choosing Your Approach

Use Purpose-Built Software If:

• You want to launch quickly (days, not weeks)
• You don't have unique tracking requirements
• You prefer to focus on your core product
• You value reliability over customization

Recommended: PromoteKit for Stripe-native tracking.

Build In-House If:

• You have highly unique attribution requirements
• You have engineering capacity to invest
• You're willing to maintain the system long-term
• You want complete control

Use Affiliate Networks If:

• You want access to established affiliate bases
• You're primarily selling one-time products
• You're comfortable with higher fees and less control

Related Resources

• Best Affiliate Software for Stripe Merchants
• The Complete Guide to Starting an Affiliate Program
• Cookie Duration: How Long Should Tracking Last?
• Automating Affiliate Payouts