> ## Documentation Index
> Fetch the complete documentation index at: https://docs.yuko.so/llms.txt
> Use this file to discover all available pages before exploring further.

# Email Blacklist

> Block disposable email domains and known fraud sources from earning loyalty rewards.

<Note>
  **Where to find this:** Shopify admin → Apps → Yuko Loyalty → Account → Email Blacklist
</Note>

## Introduction

The Email Blacklist is a list of email domains (or specific addresses) that should be excluded from earning rewards. The most common use is blocking disposable / temporary email services that fraudsters use to abuse referral programs.

## What problem this solves

Referral fraud almost always uses temporary email services — a fraudster signs up for a hundred accounts via Mailinator and rinses the friend reward. Blocking those domains kills 90% of fraud at the source.

## When to use

* Before launching the referral program.
* When you spot fraudulent referral activity.
* When onboarding to a new market with known fraud patterns.

## Overview

* Domain-level or address-level blacklist.
* Applied at customer signup and at referral attribution.
* Common defaults pre-loaded.
* Editable at any time.

## Setup

<Steps>
  <Step title="Open Email Blacklist">
    Go to **Apps → Yuko Loyalty → Account → Email Blacklist**.
  </Step>

  <Step title="Review the default list">
    Yuko ships with a curated list of well-known disposable-email domains.
  </Step>

  <Step title="Add domains or addresses">
    Enter one entry per line:

    * Domain: `mailinator.com`
    * Address: `bad-actor@example.com`
  </Step>

  <Step title="Save">
    The list applies immediately to new signups and referrals.
  </Step>
</Steps>

## How it works

* At customer creation: if the email matches a blacklist entry, the customer is created but won't earn loyalty rewards.
* At referral attribution: if the friend's email matches a blacklist entry, the referral is rejected.
* The blacklist applies prospectively — customers already created keep their existing data.

## Best practices

<Tip>**Keep the default list and add to it** as you spot specific abuse domains.</Tip>
<Tip>**Don't blacklist legitimate ESPs** like Gmail or Outlook — you'll exclude real customers.</Tip>
<Tip>**Pair with [Referrals → Program Setup → Fraud prevention](/referrals/program-setup#configure-fraud-prevention)** for layered fraud controls.</Tip>

## FAQs

<AccordionGroup>
  <Accordion title="Can I exclude a single email address?">
    Yes — add the full address (e.g., `bad-actor@gmail.com`) instead of the domain.
  </Accordion>

  <Accordion title="How do I find new disposable domains?">
    Search community-maintained lists (e.g., `disposable-email-domains` on GitHub). Your support team will also surface common offenders.
  </Accordion>
</AccordionGroup>

## Related

<CardGroup cols={3}>
  <Card title="General" icon="gear" href="/account/general">
    Store name, currency, timezone and core preferences.
  </Card>

  <Card title="Platforms" icon="shop" href="/account/platforms">
    Connected commerce platforms and multi-store setup.
  </Card>

  <Card title="Email Blacklist" icon="ban" href="/account/email-blacklist">
    Block disposable email domains and known fraud sources.
  </Card>
</CardGroup>

<CardGroup cols={2}>
  <Card title="Book a Free Setup Call" icon="phone" href="https://cal.com/rameshelamathi/yuko-demo">
    Talk to our team for personalised setup help.

    **Time:** 30 minutes
  </Card>

  <Card title="Contact Support" icon="life-ring" href="https://yuko.so/support/">
    Visit our support hub for help articles, live chat and ticket submission.
  </Card>

  <Card title="Browse the Guides" icon="book" href="/getting-started/welcome">
    Documentation across loyalty, referrals, memberships and more.
  </Card>

  <Card title="Install Yuko" icon="shop" href="https://apps.shopify.com/yuko">
    Add Yuko to your Shopify store from the Shopify App Store.
  </Card>
</CardGroup>