Spectra S1 vs S2 Plus Breast Pump: Full Comparison Medically reviewed by Suhanee Chudasama, RN-BSN | WellBefore Editorial Team Updated March 2026 · Based on verified specs and 11,700+ parent reviews TL;DR — The Only Difference Is the Battery The Spectra S1 Plus ($279.99) has a built-in rechargeable battery for cord-free pumping. The Spectra S2 Plus ($182.99) must be plugged into an outlet. That is the only difference. Both pumps deliver 270 mmHg suction, the same massage and expression modes, the same hospital-grade closed system, and the same quiet motor. Save $97 by choosing the S2 if you will always be near an outlet. Both are FSA/HSA eligible. Side-by-Side Comparison Feature S1 Plus S2 Plus Verdict Price $279.99 $182.99 S2 saves $97 Power Source Rechargeable battery + AC adapter AC adapter only (corded) S1 for portability Max Suction 270 mmHg 270 mmHg Tie Pumping Modes Massage + Expression Massage + Expression Tie Closed System Yes — backflow-protected Yes — backflow-protected Tie LCD Display Yes Yes Tie Night Light Yes Yes Tie Noise Level Whisper-quiet (<45 dB) Whisper-quiet (<45 dB) Tie Rating / Reviews ★ 4.6 · 6,400+ ★ 4.5 · 5,300+ Tie FSA/HSA Eligible Yes Yes Tie Choose the S1 If… ✓ You pump at work, in the car, or away from outlets regularly ✓ You want the freedom to move around the house while pumping ✓ You travel frequently and need a reliable cord-free option ✓ The extra $97 fits comfortably in your budget Choose the S2 If… ✓ You pump mostly at home or at a desk near an outlet ✓ You want identical performance for $97 less ✓ You prefer a slightly lighter pump (no battery weight) ✓ You plan to use insurance or FSA/HSA to cover the cost Shop Both Pumps Portable Spectra S1 Plus ★★★★★ 4.6 · 6,400+ reviews $279.99 Hospital-grade double electric breast pump with built-in rechargeable battery. Closed system, massage + expression modes, LCD display, night light. Single or double pumping. Shop S1 Plus Best Value Spectra S2 Plus ★★★★★ 4.5 · 5,300+ reviews $182.99 Hospital-grade double electric breast pump with AC power. Same closed system, massage + expression modes, LCD display, and night light as the S1. Single or double pumping. Shop S2 Plus Frequently Asked Questions Is the suction strength the same on the S1 and S2? Yes. Both the Spectra S1 Plus and S2 Plus deliver a maximum suction of 270 mmHg. They use the same motor, the same massage mode to stimulate letdown, and the same expression mode for milk extraction. You will not notice any performance difference between the two pumps. Can I use the Spectra S1 while it is plugged in? Yes. The S1 Plus works with the AC adapter or on battery power. You can pump while plugged in and the battery will charge at the same time, so it is ready for portable use whenever you need it. Does insurance cover the Spectra S1 or S2? Most health insurance plans are required to cover a breast pump under the Affordable Care Act. Coverage varies by plan — some insurers cover the S2 at no cost and allow you to upgrade to the S1 by paying the price difference. Both the S1 and S2 are FSA and HSA eligible, so you can use pre-tax dollars regardless of insurance coverage. Contact your insurer to confirm your specific benefits. Which pump is better for working moms? If you pump at the office and have a private room with an outlet, the S2 Plus works perfectly and saves you $97. If your pumping space is unpredictable, you commute long distances, or you want the flexibility to pump in a car or conference room without hunting for an outlet, the S1 Plus and its rechargeable battery are worth the upgrade. What size flanges come with the Spectra S1 and S2? Both the S1 Plus and S2 Plus include 24 mm and 28 mm flanges in the box. If you need a different size for comfort and better milk output, Spectra sells flanges separately in sizes ranging from 20 mm to 32 mm. A lactation consultant can help you find the right fit. Why Shop at WellBefore FSA/HSA Accepted on all breast pumps Free Shipping On orders $79+ 900K+ Customers served ★ 4.5 Trustpilot rating Sources Healthcare.gov — Breastfeeding Benefits & Coverage La Leche League International Trustpilot — WellBefore Reviews