The Difference Between the 8-Minute Rule and the Rule of 8s

The 8 minute rule and rule of 8s are two rules that can be commonly confused by new clinicians. But to put it simply: one is noting the actual rule while the other is its label as described in CPT manuals.

The 8 minute rule and the rule of 8s are two calculation methods for determining the number of allowed units for timed codes. If you’re treating a Medicare patient, you need to bill in accordance with the Medicare 8-minute rule. The rule is automatically applied and cannot be changed. The rule of 8s is a label for the rule published and described in the CPT code manual. It’s an optional setting that can be applied to non-Medicare insurance types. But remember: these rules are only applied to Direct-Timed Codes.

8-Minute Rule

The Medicare 8-minute rule allows a clinician to bill Medicare insurance carriers for a full unit if the service you provide lasts between 8 and 22 minutes. Because of this stipulation, it can only apply to time-based CPT codes. But the 8-minute rule does not fit every time-based CPT code or every situation. A number of factors must be met in order to bill according to the rule.

1. If your initial evaluation lasts 35 minutes and a 7 minute therapeutic exercise, you can only bill for the evaluation. In order to bill for the therapeutic exercise, the clinician would have to spend more time with the patient.
2. If you perform 30 minutes of therapeutic exercise, 15 minutes of manual therapy, and 9 minutes of an ultrasound, you need to add up the total time of the one-on-one therapy to determine how much you can bill for. In this example the clinician has seen their patient for 54 minutes, and thus can bill for 4 units.

Rule of 8s

The rule of 8s follows the same principles of the 8-minute rule, but it is calculated per service. In other words, a clinician needs to perform half the service time outlined in a timed code before she can bill for one unit of that code.

The timed codes physical therapists use typically are 15 minutes by definition, which means at least 8 minutes of a unique service must be performed to bill for one unit of that service.

It’s important to point out that the rule of 8s only applies to relevant timed codes that have 15 minutes as the usual time in the operational definition of the code. Additionally, clinicians should only apply this rule if your payer contract supports the rule.

These two rules are important for all physical therapists to know. Agile EMR makes logging all documentation surrounding these rules as efficient as possible. Our team is committed to reducing wasted time and easing clinic frustration. Schedule a demo today to improve your EMR experience!