More than 58,000 pre-schoolers were given free health checks last year, a record 92 percent.
Health Minister Jonathan Coleman says that's the highest rate since the programme began in 2008 and figures for 2015/16 are tracking even higher.
"We've also seen an increase for Maori and Pacific four-year-olds with 87 percent of Maori children and 88 percent of Pacific children reached in 2014/15," he said on Monday.
"We're seeing continued progress in reaching out to families in high-deprivation areas."
The B4 School Check looks for problems that could affect a child's learning, as well as more comprehensive health issues.
Dr Coleman says the most common findings were vision and hearing difficulties.
In the six months to December just over 2000 children were identified with possible hearing loss and referred for treatment or further assessment.