What Is Referral Marketing? How a Referral Program Works
Referral marketing rewards customers for new signups. How a referral program works, 6 reward types with costs, and how it differs from affiliate programs.
Muzahid Maruf, Founder
On this page
- 01Referral marketing compared with word of mouth
- 02What the research says about referred customers
- 03How a referral program works from click to reward
- 04Reward types and what they cost
- 05Types of referral programs
- 06Measuring whether it works
- 07Referral program or affiliate program
- 08Abuse and legal rules to plan for
- 09Running a referral program in TrackRev
Explore with AI
Opens this article inside the chosen assistant with a ready-made prompt.
Referral marketing rewards existing customers for introducing your product to others.
A referral program is the system behind it: each customer gets a unique link or code, a visitor who arrives through it is recorded, and when that visitor pays, the referrer, the friend or both earn a reward such as credit, a discount or cash.
An affiliate program uses the same plumbing with outside publishers.
Dropbox's refer page shows the pattern. When a friend signs up through your link, you both get storage: 500 MB per referral on Basic, capped at 16 GB, and 1 GB on Plus, capped at 32 GB.
Key takeaways
- A referral program rewards customers who bring in buyers. An affiliate program pays outside partners, with a median of 20% of each payment for 12 months in B2B SaaS.
- In a 2011 study of 9,814 customers of a German bank, referred customers earned about 25% more contribution margin, 82.0% were still customers after 33 months against 79.2%, and six-year value ran at least 16% higher.
- Pay after the first invoice clears and your refund window closes. On a $49 plan, a $25 referrer credit plus 20% off the friend's first 3 months costs $54.40, or 11.6% of first-year gross profit.
- Referral volume tracks your customer count: 1,000 customers produced 24 paid referrals in the worked example. Add an affiliate program for reach beyond your own base.
Referral marketing compared with word of mouth
Word of mouth happens without you. Referral marketing adds a record of who sent whom, a reward, and a rule tying the reward to a purchase.
Nielsen's April 2012 Global Trust in Advertising survey of 28,000 internet respondents in 56 countries found that 92% trusted earned media such as recommendations from friends and family, up 18% since 2007.
Employee referral programs, which pay staff for recruiting, belong to HR.
What the research says about referred customers
A paid recommendation may carry less weight than a free one, so the evidence on rewarded referrals matters. A German bank paid existing customers a 25 euro voucher per new customer.
Researchers at Goethe University Frankfurt and the Wharton School (Philipp Schmitt, Bernd Skiera and Christophe Van den Bulte) followed 5,181 referred customers and 4,633 others through September 2008 and reported the results in a Journal of Marketing paper in January 2011.
Referred customers produced 7.6 cents a day (27.74 euros a year) more contribution margin on a base of 30 cents, about 25% more, and after 33 months 82.0% were still customers against 79.2%.
Acquiring them cost about 20 euros less than customers won by mailing. The margin gap shrank over time and the retention gap did not, and six-year value came out at least 16% higher.
One bank says little about a SaaS plan, and the gain varied by segment, so run your own cohort test.
How a referral program works from click to reward
A referral program has to carry one fact, who sent this customer, from the first click to the first payment. Affiliate tracking shows where each hand-off breaks.
| Step | What happens | Where it breaks |
|---|---|---|
| 1. Issue an identifier | A link such as yourapp.com/?ref=sarah-k, a code such as SARAH20, or both. | A generic code that anyone can post on a coupon site. |
| 2. Capture the visit | The landing page stores the ref value in a first-party cookie. | Safari deletes cookies created in JavaScript after 7 days of no user interaction with your site, under WebKit's Intelligent Tracking Prevention. |
| 3. Attach it to the signup | The ref value is saved on the new account at registration. | A signup on a second device, or after cookies were cleared. |
| 4. Carry it to billing | It rides into checkout as Stripe Checkout metadata or a typed promotion code. | A checkout that never receives the value. |
| 5. Wait for payment | The reward fires on the first paid invoice, then waits out a refund window such as 30 days. | Paying at signup or at trial start. |
| 6. Deliver the reward | Credit lands on the referrer's next invoice, or cash goes out in a monthly batch. | A refund after the reward has gone. |
Links, codes and the billing side
A link records the click; a code needs none, since the friend types it at checkout.
In Stripe a code is a promotion code that maps to a coupon and can be limited to first-time customers or capped at, say, 100 redemptions. Accept both and decide in advance which wins when they disagree.
A Checkout Session and its subscription keep separate metadata fields, so set both: renewals invoice on the subscription. Coupon code tracking has more.
# 1. The friend's reward: 20% off for 3 monthscurl https://api.stripe.com/v1/coupons \ -u "<<YOUR_SECRET_KEY>>:" \ -d id=friend-20-for-3-months \ -d percent_off=20 \ -d duration=repeating \ -d duration_in_months=3 # 2. A Checkout Session that applies it and records the referrercurl https://api.stripe.com/v1/checkout/sessions \ -u "<<YOUR_SECRET_KEY>>:" \ -d mode=subscription \ -d "line_items[][price]"="<<PRICE_ID>>" \ -d "line_items[][quantity]"=1 \ -d "discounts[][coupon]"=friend-20-for-3-months \ -d "metadata[referrer]"=sarah-k \ -d "subscription_data[metadata][referrer]"=sarah-k \ -d success_url="https://example.com/welcome"Reward types and what they cost
| Reward | Example | Cost to you | Watch for |
|---|---|---|---|
| Credit for the referrer | $25 off the next invoice | $25 of revenue, only after the friend pays | Your product needs somewhere to apply credit. |
| Discount for the friend | 20% off the first 3 months | 3 months at $9.80 is $29.40 | In Stripe, a repeating coupon with duration_in_months set to 3. |
| Free months | 1 month free | $49 | It delays the first payment, so the referrer's reward waits too. |
| Cash | $50 once, sent by PayPal or Wise | $50 | Every referrer becomes a payee with a tax form. |
| Product usage | Dropbox Basic: 500 MB per referral, up to 16 GB | Storage costs and no cash | Works only when the reward is cheap for you to provide. |
| Recurring commission | 20% of each payment for 12 months | $9.80 a month, $117.60 over 12 months | Cost grows with retention, and it starts to resemble an affiliate program. |
Costs assume a $49 monthly plan.
Worked example: $49 plan, 80% gross margin
The plan earns $39.20 of gross profit a month. Give the referrer a $25 credit and the friend 20% off the first 3 months ($29.40), and rewards total $54.40 per referred customer. If the customer stays 12 months, gross profit is $470.40 at list price and $416.00 after rewards, so rewards take 11.6% of it. Month 1 alone leaves $4.40 ($39.20 less the $9.80 discount and the $25 credit). If the friend would have bought anyway, the whole $54.40 bought nothing, so a first cohort needs a comparison group.
Types of referral programs
| Type | Who is paid | Example |
|---|---|---|
| Single-sided | The referrer only | $25 credit to the referrer, nothing for the friend |
| Two-sided | Referrer and friend | Dropbox Basic: 500 MB to each side per referral |
| Milestone | The referrer, with rewards that grow | A free month at 3 referrals, a free quarter at 10 |
| Recurring commission | The referrer, monthly | 20% of each payment for 12 months |
Dropbox's April 3, 2012 post says the company first gave 250 MB per invite, then doubled that so both sides get 500 MB, and a free account could invite 32 people for 16 GB in total.
Pro accounts earned 1 GB per referral, 32 GB in total.
Measuring whether it works
Track participation, invites per sharer, invite-to-paid conversion and reward cost per paid customer, then compare referred customers' 90-day retention and revenue with everyone else's, as the bank researchers did over 33 months.
| Stage | Rate | Result |
|---|---|---|
| Customers | 1,000 | |
| Share at least once | 6% | 60 |
| Invites sent | 5 each | 300 |
| Become paying customers | 8% | 24 |
| Reward cost | $54.40 each | $1,305.60 |
Illustrative rates for a 1,000-customer base, not benchmarks.
Those 24 customers equal 2.4% of the base. Dividing new customers by existing ones gives the viral coefficient, here 0.024, and a program grows on its own only above 1.
Volume tracks customer count: 250 customers at the same rates yield 6. Compare the $54.40 with what other channels cost you per customer, and check each signup for self-referral before you count it.
Referral program or affiliate program
| Attribute | Referral program | Affiliate program |
|---|---|---|
| Who promotes | Existing customers | Outside publishers, creators and consultants |
| Example reward | $25 credit, or 20% off 3 months for the friend | Cash commission, such as 20% of each payment for 12 months |
| Cost per customer on a $49 plan | $54.40 once, from the worked example | $117.60 over 12 months if the customer stays (20% of $49, 12 times) |
| Volume limit | Your customer count and whom they know | The partners you can recruit and activate |
| Main fraud pattern | Duplicate accounts claiming the reward | Self-referral and ads bidding on your brand name |
When a referral program fits
Start here when customers already recommend you unprompted and buyers know each other, as teams and agencies with clients do, and a $25 credit is an easy reward for you to give.
When an affiliate program fits
Choose it when you need reach beyond your customers: buyers who research tools through blogs, newsletters and YouTube reviews, or a segment with no customers yet.
TrackRev's affiliate benchmark tables for Q2 2026, compiled from public Impact, PartnerStack and Awin research, put the median B2B SaaS commission at 20% for 12 months across 564 programs, and starting an affiliate program covers setting yours.
Running both works too: credit for customers, commission for outside partners.
Abuse and legal rules to plan for
Expect second accounts that claim the reward. The bank study's authors note most programs pay however long the new customer stays.
Pay only on a paid invoice, hold through your refund window (30 days, for example), cap redemptions, and use the first-time-customer restriction on Stripe promotion codes.
The Federal Trade Commission's Endorsement Guides Q&A, covering guides revised in 2023, says a disclosable connection extends past money to gifts, sweepstakes entries and deals between acquaintances.
Put a disclosure rule in your terms and on the share screen; FTC, GDPR and consent rules covers the rest.
For emailed invites, the CAN-SPAM guide says a seller who gives money, coupons or discounts for forwarding a message, or for any form of referral, may be responsible for compliance: accurate headers, a postal address, opt-outs honored within 10 business days, and penalties up to $53,088 per violating email.
Running a referral program in TrackRev
TrackRev's Affiliate Program runs referral and partner programs in one workspace.
Each advocate gets a unique link, the friend's reward (a percentage discount, free months or an extended trial) shows on the signup page, and the advocate earns cash or credit.
Cash is tracked as commission against revenue from Stripe, Polar, Lemon Squeezy or Paddle, reversed on a refund or dispute, and held for 0 to 180 days (the default is 0, so match your refund window).
You pay from a PayPal or Wise CSV export. Self-referral detection is built in, and partner revenue appears in the same channel reports as your other sources.
The free plan covers 50 links, 1,000 tracked events a month and 1 workspace, with revenue hidden.
Every paid plan includes the whole product: Starter is $39 a month for 1 workspace and up to $10,000 of commission tracked a month, Growth is $99 a month for unlimited workspaces and up to $100,000 a month, and Scale is $199 with priority support.
A checkout outside those 4 billing systems calls for a tool built for it. See two-sided referral campaigns and the Affiliate Program page.
Found this useful? Share it.
Frequently asked questions
- It is a rule set that fixes who qualifies, the reward, the trigger and the payout. "The friend's first paid invoice triggers a $25 credit" is a complete program.
- A customer who earns a $25 credit when a friend subscribes is in a referral program. A newsletter writer earning 20% of each payment from readers for 12 months is an affiliate. The tracking matches, and the people, reward size and reach differ.
- Work backward from what a customer costs elsewhere. If paid ads cost $120 per customer, a $54.40 reward package undercuts them by $65.60 and is paid only after the first invoice clears.
- After the friend's first payment clears and your refund window closes: with 30 days, a March 1 charge becomes payable March 31. The bank study's authors flag paying at signup as prone to abuse.
- Credit needs no payout rails but suits only people who keep using you. Cash suits anyone and makes each referrer a payee, so collect a tax form such as a W-9 first.
- Use a code the friend types at checkout, which avoids Safari's 7-day limit on script-written cookies. For emailed invites, the invited address is a second identifier.
Written by
Founder, TrackRev.io & Contant.io
Muzahid Maruf is the founder of TrackRev.io and Contant.io. He writes about marketing attribution, link tracking, and revenue analytics for SaaS teams.
Writes about Marketing attribution · Link tracking · Revenue analytics · SaaS growth
Stop guessing where your revenue comes from.
Set up TrackRev in about five minutes. The free plan covers 1,000 events a month, no card needed.
Start free