Fixed all-in vs. congestion pass-through — which ENGIE product should you pick?
Both fix your energy price. One also fixes a wholesale cost that the other leaves floating.
2 min read · Updated Sep 9, 2026
ENGIE's daily matrix carries two versions of every fixed-price term, and the difference shows up on your quote as a slightly lower rate on the "congestion pass-through" line. Here is what you are choosing between.
Where congestion comes from
Wholesale power in ERCOT is bought at a hub (a regional trading point) but delivered to a load zone (where you are). When transmission lines between the two are constrained, the price at your zone is higher than at the hub. That gap is called hub-to-zone congestion, and someone has to pay it.
Fixed (all-in)
The supplier estimates the congestion cost for your zone over the term, builds it into the price, and takes the risk. Your energy rate is fully fixed: if congestion turns out worse than expected, that is the supplier's problem. You pay a small premium for the certainty.
Fixed with congestion pass-through
The energy price is still fixed, but the actual hub-to-zone congestion cost each month is passed through to you at cost — no markup. In most months it is a fraction of a cent; in a hot summer with grid constraints it can be more. Over a multi-year term it has historically averaged less than the premium the all-in product charges, which is why the headline rate is lower.
How to choose
- Pick all-in if your budget needs to be exact to the cent, if you are contracting for a public body that cannot carry variable line items, or if the premium is small for your zone.
- Pick pass-through if you can absorb modest month-to-month variation in exchange for a lower expected cost, especially on longer terms where the supplier's risk premium compounds.
Both products fix your rate for the whole term and both use the same ENGIE agreement. Delivery (TDSP) charges are regulated and pass through on either.