On a 20-amp circuit feeding two or more receptacles, a 15-amp OR 20-amp receptacle is legal. A 15-amp duplex is already two receptacles — so it qualifies. The 20-amp T-slot is only required when a single receptacle is alone on the circuit.
| Circuit rating (A) | Receptacle rating (A) |
|---|---|
| 15 | 15 |
| 20 | 15 or 20 |
| 30 | 30 |
| 40 | 40 or 50 |
| 50 | 50 |
Applies to circuits serving two or more receptacles. A single receptacle on an individual branch circuit must be rated not less than the circuit — 210.21(B)(1).
"…shall conform to the values in Table 210.21(B)(3)."
"…shall be not less than the values in Table 210.21(B)(3)."
Same table, clearer words. The 2023 phrasing settles the field argument: a larger-than-table receptacle isn't forbidden.
Receptacle ratings for branch circuits serving two or more receptacles — see the table above.
A single receptacle on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.
A duplex is two receptacles by definition; 15A receptacles are listed with 20A feed-through capability.
Cord-and-plug loads not fastened in place: max 80% of the branch-circuit rating (16A on a 20A circuit).
Receptacles: Leviton 15A & 20A. Any hand tool shown on the channel is the Klein Tools version. (affiliate links — coming soon)