Wholesale summer trough
Mont Belvieu propane spot prices typically reach their annual low in May–August. Demand is at its weakest, refineries and fractionators are at peak production, and storage inventories are rebuilding. In a normal year, the summer wholesale low sits \$0.30–\$0.60/gal below the winter peak.
Off-season residential data gap
The EIA Weekly Heating Oil and Propane Survey runs only October–March. From April through September, there is no weekly residential price publication. Wholesale Mont Belvieu remains the reference for tracking summer pricing direction.
Why dealers price summer fills competitively
Summer is when dealers compete for the coming winter's commitment. Pre-buy and capped contract programmes are how dealers lock in customers for the heating season — the better the summer rate, the easier the sell. Dealers with under-committed winter routes will price more aggressively to fill them.
Summer price by region
The wholesale summer trough is national, but the retail summer floor varies by region:
- Gulf Coast PADD III: the year-round price floor for US propane; summer prices remain low
- Midwest PADD II: meaningful summer relief vs winter peaks
- Northeast PADD I: summer pricing still high vs other regions, but the cheapest local rates of the year
- Rocky Mountain PADD IV and West Coast PADD V: moderate summer relief from winter peaks
What to do with summer pricing
Two actions for residential customers:
- Pre-buy or capped contract for the coming winter — June–September window. See summer fill.
- Top off your tank at summer rates if you have capacity. Even a partial summer fill defers expensive winter top-offs.
FAQ
When is propane cheapest in the year?
Typically May through August — both at wholesale and at retail. The exact lowest week varies year to year based on production and inventory dynamics.
Should I wait until summer to buy propane?
If you're on auto-fill or will-call without a pre-buy contract, you don't get to time deliveries. If you have flexibility (large tank, light usage), summer fills do save money. The biggest savings come from pre-buy contracts signed in summer for winter delivery.