Health How much should it cost to clean air ducts? How often should air ducts be cleaned? every three to five years How much does it cost to have duct vents cleaned? The average cost of duct cleaning is $376, or between $269 and $489. Larger homes, or those with more ducts or contamination, might pay as much as $700. Clean your ducts every 5 to 7 years or as needed to help improve system efficiency. Related Posts:How do you clear a clogged air duct?Is Bubble Wrap Duct insulation a good idea?Is duct cleaning profitable?Why are rectangular ducts used?