Owners of new or extensively renovated homes in Nassau County could spread out up to $750,000 in new valuation over eight years under a tax relief legislation approved this week in the State Legislature.

Under Nassau’s first countywide reassessment in a decade, homeowners can phase-in valuation changes — up or down — over five years.

But the exemption did not apply to new homes, or those with major renovations, because the properties essentially were being assessed for the first time.

Those homeowners effectively had to pay their full assessed valuations right away, while most properties were allowed to catch up to their new values over a five-year period.

Many owners of newly constructed homes, or those with extensive renovations, complained of exorbitant tax bills .

They said they were shouldering a disproportionate share of the property tax burden because so many other properties received the phase-in exemption.

“This bill protects taxpayers and encourages both new construction and job growth during this much-needed coronavirus pandemic recovery period,” Nassau County Executive Laura Curran said in a statement.