6-inch PVC Schedule 80 Conduit Fill

Wire capacity of trade size 6 (metric designator 155) Rigid PVC Conduit, Schedule 80, for THHN, XHHW, THW and RHW conductors from 14 AWG to 1000 kcmil.

6-inch PVC Schedule 80 holds 88 × #2, 55 × 1/0 AWG, 31 × 4/0 AWG or 14 × 500 kcmil THHN conductors at 40% fill. Internal area: 25.598 in²; usable at 40%: 10.239 in².

Internal diameter

5.709 in · 145.0 mm

Total area

25.598 in² · 16515 mm²

40% fill (3+ wires)

10.239 in²

31% / 53% (2 / 1 wire)

7.935 / 13.567 in²

Maximum conductors in 6-inch PVC Schedule 80
Wire size	THHN	XHHW	THW	RHW	THHN in a nipple (60%)	THHN area (in²)
14 AWG	1055	736	736	349	1583	0.0097
12 AWG	770	565	565	290	1154	0.0133
10 AWG	485	421	421	234	728	0.0211
8 AWG	279	234	234	122	419	0.0366
6 AWG	202	173	141	98	303	0.0507
4 AWG	124	125	105	77	186	0.0824
3 AWG	105	106	90	67	158	0.0973
2 AWG	88	89	77	58	132	0.1158
1 AWG	65	66	54	38	98	0.1562
1/0 AWG	55	56	46	33	82	0.1855
2/0 AWG	46	46	39	29	69	0.2223
3/0 AWG	38	38	33	25	57	0.2679
4/0 AWG	31	32	27	21	47	0.3237
250 kcmil	25	26	22	16	38	0.3970
300 kcmil	22	22	19	14	33	0.4608
350 kcmil	19	20	17	13	29	0.5242
400 kcmil	17	17	15	12	26	0.5863
500 kcmil	14	14	13	10	21	0.7073
600 kcmil	12	11	10	8	17	0.8676
700 kcmil	10	10	9	7	15	0.9887
750 kcmil	9	9	8	7	14	1.0496
800 kcmil	9	9	8	7	14	1.1085
900 kcmil	8	8	7	6	12	1.2311
1000 kcmil	7	7	7	5	11	1.3478

Mixed wire sizes? Calculate it

Conduit type

Trade size

Run length Nipple, 24 in. or shorter (60%)

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6-inch conduit: PVC Schedule 80 vs other types

Trade size is nominal. The real inside diameter, and so the wire count, changes with the wall thickness of each raceway type.

6-inch trade size across conduit types
Conduit type	ID (in)	Area (in²)	40% (in²)	#12 THHN	#10 THHN	#6 THHN
PVC Schedule 40	6.031	28.567	11.427	859	541	225
PVC Schedule 80	5.709	25.598	10.239	770	485	202
Rigid Metal Conduit	6.093	29.158	11.663	877	552	230

Other PVC Schedule 80 sizes

Frequently asked questions

How many #12 wires fit in 6-inch PVC Schedule 80?

770 conductors of 12 AWG THHN/THWN-2 at the 40% fill limit. With thicker THW or XHHW insulation the count is 565.

What is the inside diameter and area of 6-inch PVC Schedule 80?

The internal diameter is 5.709 in. (145.0 mm) and the total cross-sectional area is 25.598 in². The usable area is 10.239 in² at 40% fill, 7.935 in² for two wires and 13.567 in² for one.

What is the largest wire I can pull three of in 6-inch PVC Schedule 80?

1000 kcmil THHN: 7 conductors fit at 40% fill. That is three current-carrying conductors with no ground; add the ground’s area and check again with the calculator if you need one.

Can I really load it with that many conductors?

For space, yes. But 770 current-carrying conductors in one raceway means heavy ampacity derating — 10 to 20 conductors are adjusted to 50% of their table ampacity. Fill tells you what fits; derating tells you what it can carry.

NECTables.com is an independent reference and is not affiliated with, endorsed by, or a substitute for the National Fire Protection Association (NFPA). NEC® and National Electrical Code® are registered trademarks of the NFPA. Values shown are commonly published engineering data and independent calculations based on the methods of NFPA 70; they are not a reproduction of the Code. Always confirm against the edition adopted in your jurisdiction, including local amendments, and consult a licensed electrician or engineer before doing electrical work.