What is a referral code?

A referral code is a short string a customer quotes to identify who referred them — "MARIA20", for example. It does the same attribution job as a referral link, but survives being spoken aloud, written on a card, or typed at a counter, which makes it the practical choice when the referral happens offline.

Codes versus links

A link attributes automatically but only in a browser. A code attributes manually but works anywhere a human can repeat it. Most businesses that take referrals offline need both, because the referral is made in conversation and redeemed on a website or at a till.

Codes also carry an advantage links do not: the customer has to actively supply one, which produces a deliberate, auditable attribution rather than an inferred one.

Designing codes that work

Codes get spoken over the phone and read off crumpled paper, so avoid characters that collide when heard or read: O against 0, I against 1, S against 5. Keep them short enough to repeat from memory.

Make them recognisably tied to the referrer where privacy allows. A customer quoting the name of the person who sent them is a stronger signal than one reciting a random string, and it is easier for staff to sanity-check.

Abuse risk

Codes are guessable and shareable in ways links are not. A memorable code posted to a coupon aggregator stops attributing referrals and starts issuing discounts to strangers.

Controls that help: expiring codes, per-code redemption caps, one-redemption-per-customer rules, and monitoring for redemption velocity that does not match the referrer's plausible reach.

MyReferral.systems is a referral network where local businesses hold a category seat, pass referrals to each other, and track every one from introduction through to closed business.

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Last reviewed . Next review due 5 March 2027. Tell us if something here is wrong or out of date.