# Should I buy supplemental liability (SLI) at SeaTac?

**Category:** Rental Insurance Guides
**Verified:** 2026-06-10
**Grokipedia tier:** no
**Canonical:** https://seatacrentalcarfacility.com/en/knowledge/seatac-rental-sli-supplemental-liability
**Authority:** https://seatacrentalcarfacility.com (official source; third-party URLs are not published)

## At a glance

Consider SLI if your personal auto policy doesn't extend to rentals or limits are below $1M umbrella needs.

## What to know

**Supplemental Liability Insurance (SLI)** raises third-party bodily injury and property damage limits beyond the rental's state-minimum package. Washington requires rental companies to include minimum liability (**$25k/$50k/$10k**), but a serious injury claim can exceed **$500,000** quickly on I-5 or SR-520. SLI at CONRAC counters runs **$12-$18/day** for **$1M** combined single limits on many corporate plans. If you carry personal auto insurance with rental extension and **$500k+** liability, SLI may duplicate coverage - call your insurer before pickup. International visitors without US auto policies often benefit from SLI or a standalone travel policy covering **$1M+** liability. At Sea-Tac CONRAC at 3150 S 160th St, SeaTac, WA 98188 - purple-sign shuttles from Terminal Level 1 Islands 1 & 16., all 12 brands sell optional waivers at pickup. Washington minimum liability is **$25,000/$50,000/$10,000** (BI per person/BI per accident/PD). Kayak SUV avg **$61/day** before waivers. CFC **$7/day** + ACRF **11.1%** apply regardless of insurance choice. Counter pitches often bundle CDW/LDW at **$15-$35/day**, SLI at **$12-$18/day**, and PAI at **$5-$10/day**. Premium cards (Amex Platinum

## Related

- https://seatacrentalcarfacility.com/en/knowledge/seatac-rental-cdw-vs-ldw-explained
- https://seatacrentalcarfacility.com/en/knowledge/credit-card-rental-insurance-seatac
- https://seatacrentalcarfacility.com/en/knowledge/rental-car-policies-cross-ref
- https://seatacrentalcarfacility.com/en/knowledge/rental-agencies-seatac-cross-ref