HDHP + HSA Strategy

What makes an HDHP

The IRS defines an HDHP each year with minimum deductibles and maximum out-of-pocket limits. For 2026:

• Minimum annual deductible: $1,700 self-only, $3,400 family.
• Maximum out-of-pocket: $8,500 self-only, $17,000 family.

These are IRS requirements. Individual plans often have deductibles above the minimum and out-of-pocket maxes below the maximum.

Only HDHPs qualify you to contribute to an HSA. A Gold plan with a $500 deductible, no matter how good, doesn't.

The HSA triple tax benefit

Covered fully in the HSA article, but the key points:

• Tax-deductible contribution (or pre-tax via payroll).
• Tax-free growth in the account.
• Tax-free withdrawal for qualified medical expenses — no time limit.

No other account in the U.S. tax code offers all three benefits simultaneously.

The optimal strategy

For healthy people who can afford to pay small medical bills from cash flow:

1. Choose the HDHP option in your employer's plan menu (if available and appropriate).
2. Contribute the maximum to your HSA each year ($4,400 self / $8,750 family in 2026, plus $1,000 catch-up at 55+).
3. Invest the HSA balance aggressively in low-cost index funds (most HSAs allow investment above a small cash floor).
4. Pay medical bills from your checking account rather than from the HSA.
5. Save the receipts — digital folder or box, organized by year.
6. Reimburse yourself years later — sometimes decades later. Tax-free withdrawal for any documented qualified medical expense, with no time limit.

This strategy converts the HSA into a supercharged retirement account. The $4,400–$8,750 annual contribution compounds tax-free for 20–40 years. In retirement, you can reimburse yourself for decades of medical expenses or withdraw for non-medical purposes (taxed as ordinary income, like a Traditional IRA, if over 65).

The math

Compare two strategies for a family earning $150k with $8,750 of available savings:

Strategy A — Traditional plan + max Roth IRA ($7,500)

• Traditional plan premiums: ~$400/month higher than HDHP
• Saves net $7,500 in Roth IRA annually
• 20 years, 7% return: Roth value ~$328,000
• Medical costs paid out of pocket normally (same either way)

Strategy B — HDHP + max HSA ($8,750)

• HDHP premiums $400/month lower than traditional (+$4,800/year)
• Contributes full $8,750 to HSA
• Saves additional $4,800 to Roth IRA (partial use, if room)
• 20 years, 7% return: HSA value ~$383,000 + Roth $210,000 = $593,000
• Tax-free for qualified medical expenses, which are typically substantial in retirement

Strategy B wins substantially because of lower premiums plus the HSA tax advantage.

Who should NOT use this strategy

People with chronic conditions or expected high healthcare use. If you have diabetes, cancer in remission, or a condition requiring frequent specialist visits, the HDHP's high deductible can mean $5,000–$15,000 out of pocket per year. The math flips.

Families planning pregnancy. Pregnancy and childbirth under an HDHP typically exhaust the family deductible and a large portion of out-of-pocket max. Lower-deductible plans may save thousands for the birth year.

People without the cash to pay medical bills. The strategy requires paying small medical bills out-of-pocket (from checking, not from the HSA). If a $500 doctor visit creates financial stress, the HDHP strategy isn't appropriate.

People who will still enroll in Medicare soon. Medicare enrollment disqualifies you from HSA contributions. If you're within a year or two of 65, the window for benefit is too short to justify.

The "paying small bills from cash" test

The strategy's central discipline is not using the HSA for current medical expenses. Many people find this counterintuitive — the money is sitting right there.

The test: can you pay a $300 doctor visit from your checking account without flinching? A $1,500 urgent care visit? A $5,000 ER bill? If yes, save the receipts and leave the HSA alone to grow. If no, fund the HSA but use it normally for current bills.

Receipt management

For the reimbursement-later strategy, receipts are your tax-free withdrawal authorization. Keep:

• Provider name and service date.
• Description of service (doctor visit, prescription, dental, etc.).
• Amount paid.
• Proof of payment (credit card statement, canceled check).

Digital photos in a cloud folder (Google Drive, Dropbox) organized by year work fine. Most people who do this diligently accumulate tens of thousands of dollars of eligible receipts by retirement.

Family situation changes

Each family member's coverage determines HSA eligibility:

• Self-only HDHP — limit is $4,400 (2026).
• Family HDHP — limit is $8,750, regardless of number covered.
• Both spouses in HDHPs — they split the family limit in any ratio they choose.
• One spouse in HDHP, other in non-HDHP — only HDHP-covered spouse contributes to their own HSA.

Changes mid-year are handled pro-rata, or via last-month rule (if HDHP-covered on December 1, treated as full-year for HSA contribution purposes, subject to testing period).

How Horizons uses this

Horizons models HDHP premiums and HSA contributions separately. The HSA can be tracked as a tax-free investment account. Healthcare expenses in the forecast can be paid from the HSA (tax-free) or from taxable accounts (after-tax), with the engine optimizing for the most tax-efficient source in retirement.