By Blissom · Updated 2026-11-04
200 A feeder sets
Most 2" EMT is pulled for 150–200 A feeders. A typical single-phase copper set:
| Conductors | Area each (in²) | Subtotal (in²) |
|---|---|---|
| 3 × #3/0 THHN (two hots and a neutral) | 0.2679 | 0.8037 |
| 1 × #6 THHN (ground, Table 250.122) | 0.0507 | 0.0507 |
| Total, 4 conductors | 0.8544 | |
| Allowed: 40% of 3.356 in² | 1.3424 |
25.5% fill. Two counted conductors, no adjustment. 3/0 copper is 200 A at 75 °C, matching the breaker; above 100 A, 110.14(C)(1)(b) lets you size from that column instead of the 60 °C one (165 A).
Dwelling services and main feeders can use the smaller sizes allowed by 310.12. This page sticks to Table 310.16.
Three-phase 200 A: when 2" is too small
On 208Y/120 V feeding mostly nonlinear load, the neutral counts. Four conductors means 80%, and 3/0 drops from 225 A to 180 A, under 200.
| Phase wire | Usable ampacity | On 200 A | Fill in 2" | Fill result | Smallest EMT |
|---|---|---|---|---|---|
| #3/0 | 180 A | too low | 33.4% | passes | 2" |
| #4/0 | 208 A | OK | 40.1% | over 40% | 2-1/2" |
Going to 4/0 fixes the ampacity but pushes fill to 40.1%. That fails by a hair, so the set needs 2-1/2" EMT. With a linear load the neutral does not count, 3/0 holds 200 A, and the 33.4% set stays in 2".
Parallel sets for 400 A
For 400 A, two sets of 3/0 in two 2" raceways is a common layout. Each pipe gets a complete set: three phases, a neutral and its own full-size ground (#3 for 400 A).
| Conductors | Area each (in²) | Subtotal (in²) |
|---|---|---|
| 4 × #3/0 THHN (phases and neutral) | 0.2679 | 1.0716 |
| 1 × #3 THHN (ground, 250.122(F)) | 0.0973 | 0.0973 |
| Total, 5 conductors | 1.1689 | |
| Allowed: 40% of 3.356 in² | 1.3424 |
34.8% fill per pipe. With linear load each set counts three and the pair carries 400 A. If the neutral counts, the pair drops to 360 A, short of 400. Parallel conductors must match in length, material, size, insulation and termination (310.10(G)).
Don't mix both sets in one raceway to save a pipe: eight counted conductors go to the 70% band.
2" EMT fill table
2" EMT: 3.356 in² inside (Chapter 9 Table 4). One conductor may fill 53%, two 31%, three or more 40%.
| Wire | THHN / THWN-2 | XHHW-2 | THW |
|---|---|---|---|
| #14 | 138 | 96 | 64 |
| #12 | 101 | 74 | 51 |
| #10 | 63 | 55 | 40 |
| #8 | 36 | 30 | 24 |
| #6 | 26 | 22 | 18 |
| #4 | 16 | 16 | 13 |
| #3 | 13 | 14 | 12 |
| #2 | 11 | 11 | 10 |
| #1 | 8 | 8 | 7 |
| #1/0 | 7 | 7 | 6 |
| #2/0 | 6 | 6 | 5 |
| #3/0 | 5 | 5 | 4 |
| #4/0 | 4 | 4 | 3 |
| 250 kcmil | 3 | 3 | 3 |
| 300 kcmil | 3 | 3 | 2 |
| 350 kcmil | 2 | 2 | 1 |
| 400 kcmil | 1 | 1 | 1 |
| 500 kcmil | 1 | 1 | 1 |
| 600 kcmil | 1 | 1 | 1 |
| 750 kcmil | 1 | 1 | 1 |
With Note 7 rounding. THW uses Annex C's larger dimensions. A bare ground counts at its Table 8 area.
Branch circuits in 2": the trap
101 #12 fit, so it is tempting to run a whole panel's worth of home runs in one 2". The bands below show why that fails:
| Wire and breaker | Fits by fill | Current-carrying limit | What stops you first |
|---|---|---|---|
| #14 on 15 A | 138 | 9 | Derating |
| #12 on 20 A | 101 | 9 | Derating |
| #10 on 20 A | 63 | 20 | Derating |
| #10 on 30 A | 63 | 6 | Derating |
The band-by-band derating table (80%, 70%, 50% and lower) is the same for every pipe size; it is on the 3/4" EMT page. The fill count includes one ground, which never counts toward the current-carrying limit.
At 41 or more, #12 is worth 10.5 A. Even on #10, the most you can protect at 20 A is 20 counted conductors: 20 circuits on shared neutrals, or 10 with their own. Two smaller raceways carry more circuits than one 2".
Grounds are not counted (310.15(F)); shared 120/240 V neutrals are not counted (310.15(E)). Ampacity is capped by the termination rating (110.14(C)), and hot locations need a 310.15(B) correction too.
Splitting the run
- Branch circuits: split into several 3/4" or 1" runs. Each raceway has its own count, so each can carry its own 9 #12.
- Feeders near 40%: 3/0 and 4/0 are stiff. If a three-phase set is close to the limit, step up a size rather than fighting the pull.
- Long or bendy runs: the 360° rule applies here too, and a pull point is cheaper than damaged insulation.
- Future upgrades: a spare empty raceway next to the feeder is often worth more than extra room in this one.
Figures follow NEC 2023, so verify against the edition your inspector enforces. Any other set can be checked in the conduit fill calculator.
Sources: NEC 2023: Chapter 9, Tables 1, 4 and 5 with Note 7 (fill); 310.15(C)(1) (adjustment for more than three current-carrying conductors), 310.15(E) and (F) (neutrals and grounds), Table 310.16, 240.4(D) and 110.14(C). Method.
Questions electricians ask
How many wires fit in 2 inch EMT?
101 #12 THHN, 138 #14, 63 #10, 5 3/0, 4 4/0 or 3 250 kcmil THHN, any insulated ground included.
Will 200 amp wire fit in 2 inch EMT?
A single-phase 200 A copper set (three 3/0 THHN and a #6 ground) fills 2" EMT to 25.5%, well within 40%. A three-phase four-wire set of 4/0 reaches 40.1%, which is over the limit.
How many current-carrying conductors can be in a 2 inch conduit?
Fill allows 101 #12, but ampacity is the real limit. On 20 A breakers #12 THHN stops at 9 current-carrying conductors and #10 at 20, in any pipe size.
Can I run parallel feeders in 2 inch EMT?
Yes, one complete set per raceway, each with the same conductors and a full-size equipment grounding conductor (310.10(G), 250.122(F)). Conductors in parallel must be 1/0 or larger.
Service and feeder fill, offline
- NEC fill for feeder and parallel sets with grounds
- Smallest trade size for any conductor mix
- Offsets and 90s for large EMT
- Box fill for the smaller runs
Android only. There is no iPhone version yet; the free calculators on this site work on any phone.
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