Security defaults or Conditional Access? You can only run one
Security defaults give every Microsoft tenant free baseline MFA. Conditional Access gives you rules by user, device and location. The two cannot run together, so know which one you are on.
Guide · 12 Nov 2026Microsoft Solutions PartnerLondon
2Ways to enforce sign-in security in Microsoft 365
3Protections security defaults switches on
1Of the two can be active at a time
Both options protect sign-ins, and many London businesses are on one without knowing which. Here is what each does, and what to do when you move from one to the other.
Overview
The two options side by side
Microsoft does not intend them to be combined.
Security defaults
A free baseline for every tenant.
- MFA registration for all users
- MFA for administrators
- Blocking of legacy authentication protocols
Conditional Access
Needs at least Entra ID P1, which Business Premium includes.
- Fully customisable rules
- Sign-in conditions based on user, device and location
- Enable policies straight away once security defaults is turned off
In detail
The switch-over gap
Turning security defaults off without a replacement leaves sign-ins less protected.
What to do
Creating Conditional Access policies means turning security defaults off.
Enable your Conditional Access policies straight away when you do.
Replace what security defaults gave you: MFA for all users, stronger MFA for admins, and legacy authentication blocked.
FAQ
Frequently asked questions
Quick answers, based on Microsoft's own documentation.
Can I use security defaults and Conditional Access together?
No. Microsoft states the two are not meant to be combined: creating Conditional Access policies means turning security defaults off, and you should enable Conditional Access policies straight away when you do.
What does security defaults switch on?
MFA registration for all users, MFA for administrators, and blocking of legacy authentication protocols.
Do I need a licence for Conditional Access?
Conditional Access needs at least Microsoft Entra ID P1. Microsoft 365 Business Premium includes Entra ID P1.
In detail
Keep reading
More from Foxcomm on keeping a London business secure and supported.
Talk to Foxcomm
Foxcomm is a Microsoft Solutions Partner and holds ISO 27001 and Cyber Essentials Plus. Book a free consultation and we will review how your current Microsoft 365 tenant is configured.