The move, which could be approved Wednesday, comes after homeowners and businesses were hit with increases that doubled their heating bills from last year's level.
It could mean utilities being required to buy natural gas supplies in long-term contracts to avoid price fluctuations.
Recent price hikes hit consumers hard enough that Colorado Attorney General Ken Salazar took the unusual step this week of writing to the Public Utilities Commission to urge passage of the new pricing rule.
''It struck me that this is an issue very important under my mission of consumer protection,'' Salazar said.
''We want to make sure that in their planning, the utilities are addressing the issue of price volatility,''' said PUC spokeswoman Barbara Fernandez.
With longer-term contracts, customers might pay slightly higher than current market prices, but they would be partially protected from rapid price hikes.
''We're definitely going to be sitting down with the PUC and working through this issue,'' said Xcel spokesman Steve Roalstad. The company has noted that entering long-term contracts now could lock them into higher prices when they may well fall once supply comes closer to demand.