Facebook

Facebook single sign-on (SSO) lets visitors join your website or app with the Facebook account they already have, instead of creating a new username and password. This article explains how it works and why it's worth offering, then walks you through connecting your own Facebook app so visitors see your brand when they click "Continue with Facebook".

In short: When a visitor clicks "Continue with Facebook", Facebook confirms who they are and shares their name, profile picture and email address with your site, so you never see or store their password. Bread & Butter supports Facebook out of the box. To show your own brand name and logo on Facebook's screen, create an app in the Facebook Developer portal, get it verified and published, then paste its App ID and App Secret into Settings, then Global Conversion Methods, in Bread & Butter.

Need a hand? Setting up developer credentials can feel a bit overwhelming. We offer a free 15-minute onboarding session to help you get this configured. Book your session with a specialist here.

What is Facebook SSO?

Facebook SSO lets people use their Facebook account to sign in to other websites and apps. Your site never receives or stores their Facebook password.

  1. A visitor clicks Continue with Facebook on your site.
  2. Facebook asks them to confirm they want to share their details with you.
  3. Facebook confirms who they are and sends your site their name, profile picture and email address.
  4. Bread & Butter creates a verified profile for them, and returning visitors are recognized with the same click.

Facebook only shares an email address when a valid one is on the person's profile. Meta's developer documentation notes the email field "will not be returned if no valid email address is available", so keep an email option available alongside Facebook.

Why offer Facebook sign-in?

Meta's apps, Facebook, Instagram, Messenger and WhatsApp, were used by an average of 3.6 billion people every day in June 2026, according to Meta's second quarter 2026 results. If your audience includes consumers, a large share of them already have an account they can use in one click.

  • Less friction. Some people leave rather than fill in another sign-up form and invent another password. A familiar button is an easy yes.
  • Borrowed trust. Visitors confirm on Facebook's own screen, which feels safer than handing a new site a password.
  • No passwords to manage. You don't handle password resets, and there's no password database to protect. If a visitor has trouble with their account, Facebook handles it.
  • More complete profiles. You get the visitor's real name and email address instead of whatever they type into a form.

Facebook works best for consumer audiences. For B2B buyers, pair it with Google, Microsoft and LinkedIn, and put the option your audience uses most at the top.

Why connect your own Facebook app?

Building Facebook sign-in yourself takes development time, and someone has to keep it working every time Facebook changes its requirements. Bread & Butter handles that for you and keeps the connection up to date.

When you first install Bread & Butter, Facebook may not show your own brand during sign-in, because it isn't yet configured for your domain. To build trust and avoid losing visitors at that step, set up your own app in the Facebook Developer portal. Visitors then see your brand name and logo when they click "Continue with Facebook".

Here is how to set it up in five steps.

Step 1: Create Your Facebook App

  1. Log in to the Facebook Developer website.
  2. Click on My Apps at the top right, then click Create App.

  3. Enter an App Name. We highly recommend using your exact company name, as this is what will appear to users during the login process. Ensure your contact email is correct, then click Next.

  4. Select Authenticate and request data from users with Facebook Login, then click Next.

  5. Choose to connect this app to a business portfolio (recommended). If you are unsure or do not have one ready, choose "I don't want to connect a business portfolio yet".

  6. Review the overview, note the required actions you'll need to complete later to publish your app, and click Create app.


Step 2: Configure Authentication & Branding Settings

This ensures your app requests the correct data and looks trustworthy to your visitors.

  1. On the Dashboard, click on the first item: "Customize the Authenticate and request data from users with Facebook Login use case".

    Find the email     permission and click Add to ensure you capture the user's email address during conversion.

    In the menu under Facebook Login, click Settings. For the Valid OAuth Redirect URIs, paste the following exact link: https://api.breadbutter.io/callback    

    Click Save Changes.

    In the collapsed left menu, click the gear icon to go to App Settings, then select Basic.

    Fill out all the required compliance and branding fields to ensure Facebook ultimately approves your app:

    • Under App domains, enter your website domain.
    • Enter the exact URLs for your Terms of Service, Privacy policy, and Data Deletion Instructions.
    • Add an App icon and choose an appropriate Category for your business.

  2. Scroll to the bottom of the page and click Add Platform. Select Website, enter your website's URL for the Site URL, and click Save Changes.


Step 3: Generate Your App Credentials

  1. Still on the Basic settings page, locate your App ID and App Secret keys. Copy and save both of these values, as you will need them to connect Bread & Butter in the final step.

Step 4: Complete Verifications & Publish Your App

Facebook requires manual business verification and data checkups before allowing your app to go live.

  1. If you see a Complete Data Use Checkup message at the top of the page, click Get Started and follow the on-screen steps to complete the process.

    Return to the Dashboard in the left menu and follow the remaining instructions to prepare and submit your app for review:

    • Business Verification: Follow the steps to officially verify your business identity. Note: Business Verification is strictly required by Facebook in order to go live.
    • App Review: Follow the steps and answer all questions required by the review team.

  2. Once approved, click Publish in the left menu, then click the Publish button to officially set your app to live mode.


Step 5: Link Your Credentials to Bread & Butter

  1. Log in to your Bread & Butter dashboard.
  2. Go to Settings in the left menu, then navigate to your Global Conversion Methods tab.
  3. Locate your Facebook connection and edit the settings to switch from Sandbox to Production Mode, then click Create New.
  4. Enter a custom name and description for your reference.
  5. Paste the App ID and App Secret you generated in the Facebook Developer portal.
  6. Click Save, and ensure the checkbox next to your new Facebook provider is enabled.

Finishing touch: use your own domain

Your brand name now appears on Facebook's sign-in screen. Visitors may still see breadbutter.io  in the address bar while they sign in. To keep them on your own domain the whole way through, set up a Custom Auth Domain in the Custom Auth Domain tab of your Bread & Butter settings. See What is a Custom Auth Domain, and how do I set it up?

Sources

Did this answer your question? Thanks for the feedback There was a problem submitting your feedback. Please try again later.