SEER2, EER2, HSPF2 and the federal minimums
What each rating measures, the DOE minimum for your state, and what ENERGY STAR and Cold Climate require on top.
Checked against the sources below on October 7, 2026
The short answer
A split heat pump has to be at least 14.3 SEER2 and 7.5 HSPF2 anywhere in the country. ENERGY STAR starts at 15.2 SEER2, 11.0 EER2 and 7.8 HSPF2. And every one of those numbers belongs to a specific indoor/outdoor pair — the same outdoor unit can clear a threshold with one indoor unit and miss it with another.
What each rating measures
| Rating | What it is | Read it as |
|---|---|---|
| SEER2 | Seasonal cooling efficiency: cooling delivered over a season divided by the electricity used. | The cooling-bill number. Higher is better. |
| EER2 | Cooling efficiency at one fixed condition: 95°F outdoors. | The hot-afternoon number. It is why the Southwest has its own minimum. |
| HSPF2 | Seasonal heating efficiency of a heat pump. | The heating-bill number. Higher is better. |
| COP @ 5°F | Heat delivered divided by electricity used, at 5°F outdoors. No units. | The cold-climate number. 1.75 means 1.75 units of heat per unit of electricity. |
The “2” means the rating was measured under the current federal test procedure, in force since 2023, which tests against more duct resistance than the old one. A SEER2 number is lower than the SEER number the same equipment would have carried — the two are not interchangeable.
The federal minimum
The national standard applies to equipment manufactured on or after January 1, 2023. For heat pumps it is the only standard: there is no regional heat pump minimum.
| Product | SEER2 | HSPF2 |
|---|---|---|
| Split-system heat pump | 14.3 | 7.5 |
| Single-package heat pump | 13.4 | 6.7 |
| Split-system air conditioner | 13.4 | — |
| Single-package air conditioner | 13.4 | — |
Air conditioners: three regions
Air conditioners installed in the Southeast or Southwest on or after January 1, 2023 have to meet a higher bar, and the Southwest adds an EER2 floor. In the North the national number applies.
| Air conditioner | Southeast | Southwest | Southwest EER2 |
|---|---|---|---|
| Split AC, under 45,000 Btu/h | 14.3 SEER2 | 14.3 SEER2 | 11.7 EER2 (9.8 if SEER2 is 15.2 or higher) |
| Split AC, 45,000 Btu/h and up | 13.8 SEER2 | 13.8 SEER2 | 11.2 EER2 (9.8 if SEER2 is 15.2 or higher) |
| Single-package AC | 13.4 SEER2 (national) | 13.4 SEER2 (national) | 10.6 EER2 |
Southeast: Kentucky, Virginia, Maryland, Delaware, Arkansas, Tennessee, North Carolina, South Carolina, District of Columbia, Oklahoma, Louisiana, Mississippi, Alabama, Georgia, Hawaii, Texas, Florida, Puerto Rico, and the U.S. territories. Southwest: Nevada, California, Arizona, New Mexico. North: every other state.
The rule that makes the pair matter
ENERGY STAR, and Cold Climate above it
ENERGY STAR certifies heat pumps under its Heat Pump Version 6.2 specification. Central air conditioners left the program in February 2026.
| ENERGY STAR | SEER2 | EER2 | HSPF2 |
|---|---|---|---|
| Split-system heat pump | ≥ 15.2 | ≥ 11.0 | ≥ 7.8 |
| Single-package heat pump | ≥ 15.2 | ≥ 10.0 | ≥ 7.2 |
| ENERGY STAR Cold Climate | SEER2 | HSPF2 |
|---|---|---|
| Split, non-ducted (mini-split) | ≥ 15.2 | ≥ 8.5 |
| Split, ducted | ≥ 15.2 | ≥ 8.1 |
| Single package | ≥ 15.2 | ≥ 8.1 |
On top of those ratings, a Cold Climate heat pump has to show three things at low temperature:
- COP at 5°F of at least 1.75.
- Heating capacity at 5°F of at least 70% of its capacity at 47°F.
- A controls verification: the unit has to reach those numbers running on its own controls, the way it would in a house — not in a forced test mode.
In the lookup
Where 47°F, 17°F and 5°F come from
They are the outdoor temperatures of the federal heating tests. The cooling ratings come from tests at 95°F and 82°F outdoors; the heating ratings from tests at 47°F, 35°F and 17°F, with an optional test at 5°F. Those are the points the certified capacities are measured at — nothing is measured in between.
How to read those points against your winter design temperature →
Tax credits and rebates in 2026
- The federal §25C tax credit is over. It is not allowed for any property placed in service after December 31, 2025. An article offering “30%, up to $2,000, through 2032” describes the law before July 2025.
- The Home Energy Rebates are run state by state. The two federal rebate programs were not repealed, and availability depends on the state. The Department of Energy points to each state energy office for status and eligibility.
- Utility and state programs set their own thresholds, usually on the tiers above.
This is a report of what the rules say, not tax advice.
Sources
- 10 CFR 430.32(c) — Energy conservation standards, central air conditioners and heat pumps — the national and regional minimums, and the list of states in each region
- U.S. Department of Energy — Regional Standards Enforcement — manufacture date in the North, installation date in the South
- ENERGY STAR — Air-Source Heat Pumps Key Product Criteria — Heat Pump Version 6.2 thresholds and the Cold Climate criteria
- ENERGY STAR — Furnace and Central Air Conditioner Sunset — central air conditioners left the program in February 2026
- 10 CFR Part 430, Subpart B, Appendix M1 (January 1, 2024 edition) — the test conditions behind the ratings
- IRS — FAQs on the changes made by Public Law 119-21 — the end of the §25C tax credit
- U.S. Department of Energy — Home Energy Rebates — state-run rebate programs
Federal rules change. This page reports what the sources said on the date above; the source is the authority, and state or local rules can be stricter. It is reference material, not legal advice and not installation guidance.