Promoting High-Value Health Care Through Flexibility for High Deductible Health Plans Act of 2018 This bill amends the Internal Revenue Code to allow the high deductible health plans that are required for a health savings account to cover up to $250 of specified services for self-only coverage (twice the amount in the case of family coverage) during a plan year without a deductible. The limit must be adjusted annually for inflation. The specified services covered by this bill include services other than preventive care that are identified under the terms of the plan. (Under current law, high deductible plans are already permitted to provide coverage for preventive care with no deductible.)