310.16: Conductor Ampacities

Allowable ampacities of insulated conductors rated up to and including 2000 volts, 60°C through 90°C, not more than three current-carrying conductors in raceway, cable, or earth.

Source: NEC 2020

The Math Shortcut

Use the Wire Ampacity Calculator

Size (AWG/kcmil)	Copper 60°C (TW)	Copper 75°C (THWN)	Copper 90°C (THHN)	Alum 60°C	Alum 75°C	Alum 90°C
14	15	20	25	-	-	-
12	20	25	30	15	20	25
10	30	35	40	25	30	35
8	40	50	55	30	40	45
6	55	65	75	40	50	60
4	70	85	95	55	65	75
3	85	100	110	65	75	85
2	95	115	130	75	90	100
1	110	130	150	85	100	115
1/0	125	150	170	100	120	135
2/0	145	175	195	115	135	150
3/0	165	200	225	130	155	175
4/0	195	230	260	150	180	205

Related NEC Tables

Table 310.15(B)(1): Temperature Correction Table 310.15(C)(1): Conductor Adjustment

Professional Usage

This data is provided for informational purposes only. Always verify with the latest edition of the National Electrical Code (NFPA 70) and consult with a licensed electrical professional or AHJ (Authority Having Jurisdiction) before performing any electrical work.

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Size (AWG/kcmil)	Copper 60°C (TW)	Copper 75°C (THWN)	Copper 90°C (THHN)	Alum 60°C	Alum 75°C	Alum 90°C
14	15	20	25	-	-	-
12	20	25	30	15	20	25
10	30	35	40	25	30	35
8	40	50	55	30	40	45
6	55	65	75	40	50	60
4	70	85	95	55	65	75
3	85	100	110	65	75	85
2	95	115	130	75	90	100
1	110	130	150	85	100	115
1/0	125	150	170	100	120	135
2/0	145	175	195	115	135	150
3/0	165	200	225	130	155	175
4/0	195	230	260	150	180	205

Size (AWG/kcmil)	Copper 60°C (TW)	Copper 75°C (THWN)	Copper 90°C (THHN)	Alum 60°C	Alum 75°C	Alum 90°C
14	15	20	25	-	-	-
12	20	25	30	15	20	25
10	30	35	40	25	30	35
8	40	50	55	30	40	45
6	55	65	75	40	50	60
4	70	85	95	55	65	75
3	85	100	110	65	75	85
2	95	115	130	75	90	100
1	110	130	150	85	100	115
1/0	125	150	170	100	120	135
2/0	145	175	195	115	135	150
3/0	165	200	225	130	155	175
4/0	195	230	260	150	180	205

Size (AWG/kcmil)	Copper 60°C (TW)	Copper 75°C (THWN)	Copper 90°C (THHN)	Alum 60°C	Alum 75°C	Alum 90°C
14	15	20	25	-	-	-
12	20	25	30	15	20	25
10	30	35	40	25	30	35
8	40	50	55	30	40	45
6	55	65	75	40	50	60
4	70	85	95	55	65	75
3	85	100	110	65	75	85
2	95	115	130	75	90	100
1	110	130	150	85	100	115
1/0	125	150	170	100	120	135
2/0	145	175	195	115	135	150
3/0	165	200	225	130	155	175
4/0	195	230	260	150	180	205