Calculate commercial electrical service size per NEC Article 220 Part IV. Includes lighting, receptacle, kitchen, motor, and HVAC loads with applicable demand factors.
Based on NEC 2023 Article 220 Part IV, Tables 220.12, 220.42, 220.44, 220.56
Professional Verification Required: All calculations are for reference and estimation purposes only. Results must be verified by a licensed Professional Engineer (PE), licensed electrician, or qualified person before use in any installation, design, or permit application.
Reference: NEC 2023 Article 220 Part IVRecommended Service Size
480V 3-Phase
Consider a larger service for expansion
Unit loads per occupancy type. Ranges from 0.25 VA/sqft (warehouse) to 3 VA/sqft (barber/beauty shop).
Hospitals, hotels, and warehouses: 100% first 12,500 VA, 50% remainder. All others: 100%.
First 10,000 VA at 100%, remainder at 50% for commercial occupancies.
1-2 units: 100%, 3: 90%, 4: 80%, 5: 70%, 6+: 65% demand factor for commercial cooking equipment.
Largest motor at 125% of FLC, all remaining motors at 100% of FLC.
When heating and cooling are non-coincident, only the larger load is included.
IMPORTANT LEGAL DISCLAIMER
For Reference Only: This calculator is provided for educational and informational purposes only. It is not intended to be a substitute for professional engineering design, advice, or certification.
Code Compliance: Calculations are based on the 2023 National Electrical Code (NEC®). However, local codes, amendments, and Authority Having Jurisdiction (AHJ) requirements vary by location and may supersede standard NEC requirements.
Verify with Your AHJ: Local Authority Having Jurisdiction (AHJ) requirements take precedence over all general code references. Contact your local building department or electrical inspector to confirm applicable codes, amendments, and permit requirements before beginning any electrical work.
No Liability: SparkShift, LLC and its affiliates assume no liability for errors, omissions, or the use/misuse of this tool. Users are solely responsible for verifying all results against applicable codes and standards before installation. Always consult a licensed electrician or Professional Engineer (PE).
NEC Reference: NEC 2023 Article 220 Part IV, Tables 220.12, 220.42, 220.44, 220.56
© 2026 SparkShift, LLC. Calculations are for reference only.
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