What is the active rules per type?

Only one lead assignment, one case assignment, and one escalation rule active at a time.

What is the case assignment rule size?

Up to 3000 entries, including 300 formula entries.

In order; first matching entry wins and evaluation stops.

A user or a queue; assigned users must be active with Read on the object.

Default Web-to-Lead owner, the admin importing leads, or the default case owner (Support Settings).

Template goes to the new owner; no template, no email.

Up to five, each with its own Age Over.

Escalation actions only run during their associated business hours.

Choosing the right automation tool | Platform Administrator Study Guide

Fact	Detail	Source
Active rules per type	Only one lead assignment, one case assignment, and one escalation rule active at a time	Assignment Rule Guidelines (opens in a new tab)Escalation Rules (opens in a new tab)
Case assignment rule size	Up to 3000 entries, including 300 formula entries	Assignment Rule Guidelines (opens in a new tab)
Entry evaluation	In order; first matching entry wins and evaluation stops	Assignment Rules (opens in a new tab)
Assignment rule assignee	A user or a queue; assigned users must be active with Read on the object	Assignment Rules (opens in a new tab)
No entry matches	Default Web-to-Lead owner, the admin importing leads, or the default case owner (Support Settings)	Assignment Rules (opens in a new tab)
Assignment rule email	Template goes to the new owner; no template, no email	Assignment Rules (opens in a new tab)
Escalation actions per entry	Up to five, each with its own Age Over	Escalation Rules (opens in a new tab)
Business hours	Escalation actions only run during their associated business hours	Escalation Rules (opens in a new tab)
Auto-response rules	One active for leads and one for cases; first matching entry picks the template	Auto-Response Rules (opens in a new tab)
Default Workflow User	Set on Process Automation Settings; used when the triggering user is inactive	Scheduled Paths (opens in a new tab)