Even though she claims she paid off her nearly $1 million bill to Uncle Sam before sentencing.
A judge in Newark, New Jersey dished out the sentence and told Hill that after she completes her stint behind bars, she'll spend 3 more months on house arrest ... followed by 9 months of supervised release.
Before the hearing, Hill's attorney told the media the singer scraped together more than $970,000 to repay her debt to the government.
The 37-year-old former Fugee pled guilty last year to three counts of tax evasion for failing to file returns on $1.8 million she earned from 2005 to 2007. Lauryn's attorney asked for mercy because of her charity work and 6 kids ... but the judge wasn't buying it.
During the hearing, the judge ordered Hill to report to prison by July 8. It's unclear where Hill will serve her time.