The One Big Beautiful Bill Act permanently extends and structurally reforms the Opportunity Zones program, transitioning it into a permanent feature of the tax code with rolling decennial designations rather than a temporary program. It narrows eligibility criteria by lowering the low-income community income threshold to 70 percent, eliminates the previous contiguous tract allowance, removes the seven-year step-up incentive while preserving the five-year deferral and ten-year capital gains exclusion, and introduces enhanced benefits and reduced substantial improvement thresholds for rural opportunity funds.