P on a tire: P-metric (passenger)

A passenger car tire rated against the North American Tire and Rim Association tables.

What it changes

Fitted to a light truck, SUV, pickup, van or minivan, a P-metric tire's load capacity is divided by 1.10 before it counts. That is a federal requirement, not a manufacturer's caution, and it is why a P-metric size cannot simply stand in for the LT size a truck was built around.

Where it sits: Immediately before the section width.

The 1.10 factor

A P-metric or Euro-metric tire fitted to a light truck, SUV, pickup, van or minivan has its rated load divided by 1.10. A tire rated 3086 lb is worth 2805 lb in that service. Both manufacturer bulletins cited attribute the factor to federal motor vehicle safety standards, and both apply it to Euro-metric as well as P-metric. An LT tire takes no such reduction.

Divide the rated load by 1.1. A tire rated 3086 lb is worth 2805 lb in that service.

Questions

What does P mean on a tire?
A passenger car tire rated against the North American Tire and Rim Association tables. Fitted to a light truck, SUV, pickup, van or minivan, a P-metric tire's load capacity is divided by 1.10 before it counts. That is a federal requirement, not a manufacturer's caution, and it is why a P-metric size cannot simply stand in for the LT size a truck was built around.
Where does the P appear on the sidewall?
Immediately before the section width.
Does a P tire carry less on a truck?
A P-metric or Euro-metric tire fitted to a light truck, SUV, pickup, van or minivan has its rated load divided by 1.10. A tire rated 3086 lb is worth 2805 lb in that service. Both manufacturer bulletins cited attribute the factor to federal motor vehicle safety standards, and both apply it to Euro-metric as well as P-metric. An LT tire takes no such reduction.

Where these figures come from

Published values here were read from 3 independent sources:

These are independent publishers, not independent measurements. Each one reproduces a table originally set by a standards body, so agreement between them shows a value was transcribed correctly, not that the underlying table is right. Where a figure is safety relevant, check it against the tire manufacturer's own data before relying on it.

Whether Euro-metric tires take the 1.10 light truck derating: yes - the bulletin's heading and text both read 'P-metric or metric tire' (ST-NITTO) against yes - 'When P-metric or metric tire are installed on light trucks' (ST-NEXEN). Retail and forum sources are split, with several stating that the derating applies to P-metric only. Both tire manufacturer technical bulletins consulted state it applies to metric (Euro-metric, also called hard metric) as well, and both attribute the rule to federal motor vehicle safety standards. This site follows the two manufacturer bulletins and flags the split, because the conservative reading is also the one the primary-facing documents give.