A bill to amend the Natural Gas Policy Act of 1978 to provide that interstate pipelines be subject to a prudence standard for their natural gas purchases in order to pass through the cost of such purchases to their customers if the pipelines are not subject competition for sales to their customers.

Amends the Natural Gas Policy Act of 1978 to prohibit an interstate pipeline from passing on to its customers cost increases in the natural gas it purchases from its suppliers (cost passthroughs) if the price paid by the pipeline for the natural gas was not prudent and if the pipeline has no significant sales competition.