Quick answer
PropelAuth - PropelAuth wins for most builders who need B2B auth on a free tier, because its free plan gives more immediately useful org and tenant controls, while Auth0 wins if you need a larger free MAU cap and broader general-purpose identity coverage.
How the free tiers compare
These two free tiers are aimed at different shapes of auth problems. Auth0 is the better fit if you want a more general identity platform with a much higher free MAU ceiling, social logins, passwordless, SCIM, and a small but real path toward enterprise-style features. PropelAuth is narrower but more builder-friendly for B2B apps: unlimited organizations, unlimited waitlist users, custom domain support, 2FA, RBAC, and a free tier that keeps the core multi-tenant patterns intact. The biggest difference is not just user caps, but what stays usable before you pay. Auth0’s free plan is more restrictive on org count and custom domains, while PropelAuth is more generous for SaaS-style multi-tenant apps. Once you pay, Auth0 starts cheaper, but PropelAuth’s paid plans are more aligned with B2B auth workflows and add user-overage pricing.
Auth0 vs PropelAuth free tier, side by side
| Auth0FTV 52 | PropelAuthFTV 63 | |
|---|---|---|
| Monthly active usersAuth0 gives the larger free MAU cap. | Up to 25,000 | 10,000 |
| OrganizationsPropelAuth is much more generous for multi-tenant apps. | 5 | Unlimited |
| Custom domainAuth0 also says credit card verification is required for the custom domain. | 1 | Included |
| Enterprise connections / SSOPropelAuth’s unlimited SSO only appears on the paid plan. | 1 enterprise connection; self-service SSO | Unlimited SAML / enterprise SSO connections in Growth |
| SCIMAuth0 includes SCIM in free, while PropelAuth gates it higher up. | Included | Not listed on free; Growth Plus adds SCIM / Directory sync |
| Audit log retentionPropelAuth states this in the free tier. | Not specified | 30-day audit log retention |
After you outgrow the free tier
Auth0’s next step is a flat $35/month Essentials plan, then $240/month Professional, with enterprise pricing by sales. PropelAuth starts at $150/month Growth, then $500/month Growth Plus, then custom enterprise pricing. Auth0 is cheaper to enter paid usage, but PropelAuth’s paid plans are built around B2B SaaS needs and add overage pricing for extra MAUs. For small teams staying under free limits, both are free; once you outgrow them, Auth0 is the lower-cost paid entry, while PropelAuth becomes more expensive but includes more org-centric features.
Cost at real usage
| Usage | Auth0 | PropelAuth |
|---|---|---|
| 15,000 MAUs / monthPropelAuth Growth includes 10,000 MAUs and charges $0.05 per additional MAU, so 5,000 extra users adds about $250 to the $150 base. | Free (within 25,000 MAU cap) | ~$400/mo est. |
| 25,000 MAUs / monthPropelAuth Growth: $150 base + 15,000 extra MAUs at $0.05 each. | Free (within tier) | ~$900/mo est. |
| 50,000 MAUs / monthAuth0’s provided paid plans top out at 500 MAUs for listed flat pricing, so the input does not give a rate for 50,000 MAUs. | Contact sales / varies by usage | ~$2,150/mo est. |
Estimates, not quotes. Usage-based rates change - verify with the vendor's pricing page before committing.
When to pick each one
Pick Auth0 when…
- You need up to 25,000 monthly active users on the free tier.
- You want hosted auth for a broader mix of app types, not just B2B SaaS.
- You need passwordless, social connections, SCIM, and a small number of organizations.
- You are okay with tighter org limits and a free plan that is more cap-driven than workflow-driven.
Pick PropelAuth when…
- You are building a B2B SaaS with tenants, org management, and waitlist flows.
- You need unlimited organizations on the free tier.
- You want custom domain support plus 2FA and RBAC without jumping to paid.
- You expect to use multi-tenant auth patterns early and want them to work on free.
- You want an auth layer that is more opinionated around enterprise SaaS workflows.
Bottom line
For the most common builder case, PropelAuth is the better free-tier pick if you are building a B2B SaaS with orgs, RBAC, and tenant workflows. Auth0 is the better free-tier pick if your main concern is a higher MAU ceiling or a more general identity stack. If you expect to stay free for a while, PropelAuth is easier to use for SaaS patterns. If you expect to pay sooner and want the lowest listed entry price, Auth0 starts cheaper.
Read the full listings: Auth0 and PropelAuth. Scores use the FTV methodology at /ftv. Browse more head-to-heads on /compare, or see the top-ranked free tiers on /top.