2026 Firebase Authentication’s latest pricing explained and the best alternatives

Firebase Authentication pricing at a glance#

Short answers first, details below. All prices come from Google's official pricing pages (Firebase pricing, Identity Platform pricing) as of July 2026. This guide covers Firebase Authentication only; Firestore, Hosting, and other Firebase products bill separately.

• Email, social, and anonymous sign-in are free up to 50,000 MAU, on both the Spark (free) and Blaze (pay-as-you-go) plans. Past 50K, rates start at $0.0055 per MAU.
• Phone sign-in is never free. Since September 2024, SMS verification requires the Blaze plan with a billing account attached. You pay for every SMS OTP sent: $0.01 in the US and Canada, up to $0.46 in the most expensive regions. The first 10 SMS per day aren't billed.
• SAML and OIDC sign-in costs $0.015 per MAU after the first 50 users, and requires the Identity Platform upgrade.
• The costs that surprise teams are SMS fees, SAML/OIDC per-MAU charges, and features that require the Identity Platform upgrade: TOTP MFA, blocking functions, and audit logging. The upgrade itself is free to enable; you pay for what you use on top of it.

What is Firebase Authentication?#

Firebase Authentication is the identity service inside Firebase, Google's backend-as-a-service platform. It handles sign-up and sign-in for web and mobile apps with methods like email/password, phone verification, social logins, and SAML/OIDC federation, and it plugs directly into Firestore, Cloud Functions, and the rest of the Firebase stack.

You can use Firebase Authentication on its own. There's no need to pay for or integrate other Firebase services if authentication is all you want. The catch is understanding what's free, what needs the Identity Platform upgrade, and where the bill grows as you scale.

What features are included in Firebase Authentication?#

• Email credential authentication:
  • Users sign up with an email address and password.
• Email passwordless login and verification:
  • Login with email link
  • Email address verification
  • Password recovery
  • Works with Firebase's built-in email service or your own SMTP server.
• Phone login via SMS:
  • Login with a mobile phone number and a verification code.
  • Uses Firebase's built-in SMS service only, and requires the Blaze plan with a billing account (a policy Google introduced in September 2024).
• Anonymous login:
  • Temporary accounts that let users try your app before signing up. If they register later, the anonymous account upgrades to a regular one so they keep their data.
• Social login with prebuilt providers:
  • Google, Facebook, Play Games, Game Center, Apple, GitHub, Microsoft, Twitter, and Yahoo.
• Custom federated identity providers:
  • SAML (web only) and OpenID Connect providers beyond the prebuilt list. Requires the Identity Platform upgrade.
• Multi-factor authentication:
  • SMS and TOTP (authenticator apps). Both require the Identity Platform upgrade. There's no WebAuthn or passkey factor, and as of July 2026 Firebase hasn't shipped passkey sign-in at all (the Auth emulator gained mock passkey support in mid-2026, but nothing is available in production).
• Custom templates:
  • Custom email templates for verification, password reset, email change, and MFA enrollment notices, plus custom SMS templates.
• Advanced settings:
  • User account linking: link accounts that share an email, or keep one account per identity provider.
  • User actions: enable or disable sign-up, account deletion, and email enumeration protection.
  • Sign-up quota: cap the number of new email/password and anonymous accounts created per day from a single IP address.
  • Password policy: adjust complexity requirements for email/password users.
  • Authorized domains: whitelist the domains Firebase can redirect to after sign-in.
  • SMS region policy: allow or deny SMS delivery per region, which matters for toll fraud protection.
  • Blocking functions: run custom code that modifies the result of registration or sign-in. Requires Identity Platform.
• User activity and audit logging:
  • Monitor and log administrative access and end-user activity. Requires Identity Platform.
• Cross-platform SDKs:
  • iOS, Android, Flutter, Web, C++, and Unity, plus prebuilt UI libraries.
• User management:
  • Add, disable, and delete users, and reset passwords from the Firebase console.

How does Firebase Authentication pricing work?#

Firebase Authentication has two plans: the Spark plan (free) and the Blaze plan (pay-as-you-go). On top of either plan sits an optional upgrade called Firebase Authentication with Identity Platform, which adds MFA (SMS and TOTP), SAML/OIDC providers, blocking functions, audit logging, multi-tenancy, and an enterprise SLA.

A point that confuses almost everyone: Identity Platform has no price tag of its own. Enabling it is a free switch, not a migration, and there's no license fee. What you pay are the usage rates that come with it: the Tier 1 and Tier 2 MAU rates and the SMS fees in the tables below. When Google documents Authentication pricing, the numbers live on the Identity Platform pricing page for exactly this reason.

Key differences between plans#

One footnote on limits: projects that upgrade to Identity Platform but stay on the free Spark plan get daily caps of 3,000 active users per day for Tier 1 and 2 per day for Tier 2.

Pricing breakdown#

Two billing details worth knowing:

• Inactive users are stored at no cost. Only users who authenticate during the month count as MAU.
• Anonymous users don't count toward billable MAU when automatic cleanup is enabled, and Google has enforced automatic cleanup of stale anonymous accounts for all projects since April 2024. The account storage cap for anonymous users is 100 million.

What do Firebase phone authentication and SMS OTP cost?#

SMS is where Firebase Authentication bills surprise teams most, so it deserves its own math.

• You need Blaze. Since September 2024, phone authentication requires a Cloud Billing account. There's no SMS allowance on Spark.
• Price depends on the destination country. Google publishes a table covering about 249 regions. Some current examples per SMS sent: US $0.01, Canada $0.01, Japan $0.03, UK $0.05, India $0.07, Germany $0.10, Indonesia $0.35, and up to $0.46 at the top of the table.
• The first 10 SMS per day are free, which covers development and little else.
• Every send is billed, including OTP codes that users never enter. Without the Identity Platform upgrade there's a cap of 3,000 SMS sent per day; with it, no limit. The SMS region policy and reCAPTCHA-based toll fraud protection help contain abuse, but a bot hitting your sign-up form in an expensive region can still generate real costs.

A quick scenario: 20,000 phone sign-ins per month from users in Germany costs 20,000 x $0.10 = $2,000 per month, before you've paid for anything else. The same volume in the US costs $200.

Firebase Phone Number Verification: the SMS-free option#

Google shipped a separate product called Firebase Phone Number Verification in May 2026. It verifies numbers through carrier SIM data instead of SMS codes, so there's no OTP to type and no per-message fee. The catch: it's carrier-dependent (10+ carriers across 6 regions at launch) and priced separately. For apps with users concentrated on supported carriers it can cut SMS spend, but it doesn't replace SMS OTP in general.

Worked examples#

Firebase Authentication is mostly a B2C product, so the most useful model isn't a single snapshot: it's what happens to the bill as a consumer app grows. Here's one trajectory, using the official rates. The user volumes are assumptions; the math is not.

Stage 1, launch: 8,000 MAU with email and Google sign-in, no phone auth

• Everything is Tier 1 and under 50,000 MAU.
• Total: $0/month

Stage 2, traction: 60,000 MAU, phone sign-in added, 20,000 SMS per month to US numbers

• First 50,000 MAU: free; 10,000 x $0.0055 = $55
• SMS: about 300 free (10/day), 19,700 x $0.01 = $197
• Total: about $252/month

Stage 3, scale: 250,000 MAU worldwide, 100,000 SMS per month (60,000 US, 40,000 India)

• First 50,000 MAU: free; next 50,000 x $0.0055 = $275; next 150,000 x $0.0046 = $690
• SMS: 60,000 x $0.01 = $600; 40,000 x $0.07 = $2,800
• Total: about $4,365/month, and SMS is 78% of it

The shape of that curve is the real lesson: MAU charges grow politely, SMS grows with your traffic and your geography. The same app with users concentrated in Indonesia ($0.35 per SMS) would pay five times more for the same sign-in volume.

One more scenario for B2B mixes, mirroring Google's own example on the Identity Platform pricing page:

Enterprise SaaS: 45,000 email MAU plus 77,000 SAML/OIDC MAU

• 45,000 Tier 1 MAU: free (under 50K)
• First 50 Tier 2 MAU: free; 76,950 x $0.015 = $1,154
• Total: about $1,154/month

Notice what actually drives each bill. It's rarely the Tier 1 MAU rate: it's SMS volume and SAML/OIDC seats. If you budget for anything, model those two against your own user mix.

When to use Firebase Authentication, and its pros and cons#

Pros of Firebase Authentication#

1. Quick integration:
   • Prebuilt SDKs and UI libraries for iOS, Android, Web, and more.
   • Email, social, phone, and anonymous sign-in out of the box.
2. Google infrastructure and security:
   • TLS everywhere, SOC 1/2/3 and ISO 27001 attestations, GDPR and CCPA support pages. Note that HIPAA BAA coverage requires Identity Platform, not plain Firebase Auth.
3. Generous free tier for simple apps:
   • 50K MAU free suits startups and MVPs, as long as you stay off SMS and SAML/OIDC.

Cons of Firebase Authentication#

1. Thin above the authentication layer:
   • No built-in RBAC or organization management. MFA is SMS and TOTP only, with no passkey support as of July 2026.
2. Bills that scale with usage patterns, not plans:
   • SMS fees and per-MAU SAML/OIDC charges grow with traffic, and there's no flat-rate option. Estimating costs means modeling your user mix, not reading a price card.
3. Partial IAM coverage and ecosystem coupling:
   • Authorization, consent management, and richer audit trails need other tools. The deeper you integrate with Firestore and Cloud Functions, the harder a later migration becomes.

When is Firebase Authentication a good fit?#

• Early-stage apps: prototypes and MVPs that need free, fast sign-in.
• Google-centric stacks: if the app is built around Firestore, Cloud Functions, and Firebase Hosting, the native integration is hard to beat.
• Simple requirements: no enterprise SSO, no per-organization roles, no advanced MFA.

If that's you, stay. Migration has a real cost, and "zero B2B requirements" is a legitimate long-term state for plenty of consumer apps.

When should you look at alternatives?#

Teams that migrate off Firebase Auth rarely leave because it broke. They leave because the business model matured: enterprise clients start asking for SAML SSO, roles, and organization management that Firebase doesn't have natively; European customers raise data residency questions (Firebase Auth stores user data only in the US); or the stack has quietly grown into Firebase for consumers plus a second provider for business accounts, and keeping them in sync stops being worth it. The Logto vs Firebase comparison walks through these migration triggers in detail.

In short, start evaluating alternatives when:

• B2B requirements arrive: you need organizations, RBAC, or SAML/OIDC connections without per-MAU pricing.
• You're consolidating a split stack: one system for consumer and business users instead of two.
• Budget predictability matters: you'd rather pay a flat monthly price than model SMS and MAU curves.
• You want stronger MFA: WebAuthn passkeys today, not on a roadmap.

Frequently asked questions#

Is Firebase Authentication free?#

Partly. Email, social, and anonymous sign-in are free up to 50,000 MAU on both plans. Phone sign-in is never free: SMS OTP requires the Blaze plan and bills per message sent. SAML/OIDC sign-in costs $0.015 per MAU after the first 50 users.

How much does the Identity Platform upgrade cost?#

Nothing by itself. Enabling Identity Platform is free and there's no license fee. What it adds is billed by usage: SAML/OIDC users at $0.015 per MAU after the first 50, SMS at regional rates, and the Tier 1 MAU rates past 50,000 on Blaze. The worked examples above all assume Identity Platform is enabled.

How does Firebase calculate MAUs?#

A monthly active user is any user who authenticates within the calendar month. Logging in multiple times still counts as one MAU. Inactive users cost nothing, and anonymous users are excluded when automatic cleanup is enabled.

What are the hidden costs of Firebase Authentication?#

• SMS fees ($0.01 to $0.46 per message, by region), billed on every send.
• SAML/OIDC at $0.015 per MAU after the first 50.
• Features that quietly require the Identity Platform upgrade: TOTP MFA, blocking functions, audit logging, multi-tenancy.

Is Firebase Authentication HIPAA compliant?#

Firebase Authentication is not on Google Cloud's list of HIPAA BAA covered products. If your app handles PHI, Google's guidance points to Identity Platform, the Google Cloud product, under the Google Cloud BAA. Plan for that distinction before building healthcare flows on plain Firebase Auth.

Is Firebase Authentication suitable for enterprise use?#

It covers authentication well, but there's no built-in RBAC or organization management, and MFA tops out at SMS and TOTP. Teams with B2B or compliance requirements usually pair it with other tools or pick a dedicated identity platform.

Firebase Authentication alternatives#

The alternative space splits roughly into open-source stacks you run or host (Ory, Keycloak), component-first developer tools (Clerk), enterprise SSO specialists (WorkOS), and API-first platforms (Stytch). Pricing models differ more than feature lists do, so compare the billing math for your user mix, not just the checkboxes.

Logto takes the flat-pricing route. The free plan includes 50,000 MAU, 50,000 tokens, and a custom domain, with no credit card required. The Pro plan is $24 per month with unlimited MAU: you pay for capabilities, not per user. MFA with all factors, including TOTP and WebAuthn passkeys, is a $48 add-on. Organizations for multi-tenant SaaS apps are $48 for unlimited organizations, and enterprise SSO is $48 per connector. It follows OIDC, OAuth 2.1, and SAML standards, ships SDKs for 30+ frameworks, and the core is open source, so you always have a self-hosting exit if you ever want off the cloud.

For a concrete scenario (a SaaS app with 10,000 users, multi-tenancy, MFA, and 2 enterprise SSO connections), Logto costs $24 + $48 + $48 + (2 x $48) = $216 per month, flat. The same setup at 40,000 users still costs $216, because nothing in the bill scales with MAU. The plan includes 50,000 tokens per month, with usage past that billed at $0.08 per 100 tokens.

For a feature-by-feature breakdown and the reasons teams switch, see the full Logto vs Firebase Authentication comparison, or start on the free plan: 50,000 MAU with a custom domain included, no credit card required.