ELECTRONIC Road Pricing (ERP) rates at certain roads and expressways will go up by up to $1.

The new rates, which kick in from May 6, will affect five gantries on the Central Expressway and the Bukit Timah Expressway.

There are four affected gantries on the southbound Central Expressway after Braddell Road and on the Pan-Island Expressway slip road into the southbound CTE.

The current rate is $4 from 8.30am to 9.00am, and $1 from 9.00am to 9.30am.

The revised rates will mean a $5 surcharge from 8.30am to 9.00am, and $2 from 9.00am to 9.30am

Meanwhile, the rates will be reduced at a relocated gantry along Nicoll Highway near Ophir Flyover, which starts operating on May 6.

The rates for the other gantries remain unchanged. The next rate review will be in May.