Short answer — it depends on what you value (lowest price, newest cars, luxury, easy airport pickup, long-term rentals). Based on recent industry studies and reader awards, here are the top U.S. options by category and why:

Top picks

• National — Best overall for customer satisfaction and business travelers (Emerald Club perks: skip the line, choose from the Emerald Aisle). Ranked #1 in J.D. Power’s 2024 North America Rental Car Satisfaction Study and highly rated in consumer surveys. (jdpower.com, consumerreports.org)
• Enterprise — Best for neighborhood locations and strong customer service (huge U.S. network and lots of non‑airport branches). High J.D. Power placement and consistently praised for service. (jdpower.com, traveldailynews.com)
• Sixt — Best for premium/upscale fleet (newer luxury and European models) and a modern booking/tech experience; earned reader awards in 2024–2025. Good choice if you want higher-end cars. (businesswire.com, about.sixt.com)
• Alamo — Great for leisure travelers and families (airport convenience and value). Frequently rated highly by travel‑readers. (travelnowlife.com, jdpower.com)
• Avis / Budget / Thrifty — Avis for business and frequent renters, Budget/Thrifty for lower-cost options; these brands appear regularly in industry rankings but performance varies by location. (jdpower.com, forbes.com)

Notes on choosing and saving

• “Best” varies by location and date — branch-level service and vehicle condition differ a lot, so compare nearby locations. (consumerreports.org)
• Watch total cost: taxes, airport fees, young‑driver surcharges, prepaid tolls, and optional insurance add up. Consumer Reports’ survey shows average daily costs and recommends reading the rental agreement carefully. (consumerreports.org)
• Loyalty programs (National’s Emerald Club, Enterprise Holdings’ programs, Avis Preferred) can save time and money if you rent often. (jdpower.com, prnewswire.com)
• Digital/fast pickup options are increasingly important — J.D. Power notes mobile tools and touchless pick‑up are shaping satisfaction. (jdpower.com)

If you want a single quick recommendation:

• For the smoothest overall experience (airport or business): National or Enterprise. (jdpower.com, consumerreports.org)
• For luxury/newer cars and a modern app/experience: Sixt. (businesswire.com, about.sixt.com)

Sources (selected): J.D. Power 2024 North America Rental Car Satisfaction Study; Consumer Reports (spring 2024 member survey and rental tips); recent reader awards (Travel + Leisure, USA TODAY). (jdpower.com, consumerreports.org, about.sixt.com)

If you’d like, I can: compare rates and fees for a specific city and date, or show which brands have the best loyalty perks for frequent rentals.