"Congratulations my friend Bibi @netanyahu! Recall our New York meeting last September warmly," Modi tweeted in Hebrew.
Netanyahu secured a stunning win against all odds in Israel's closely-fought general elections.
"Against all odds, we achieved a great victory for the Likud," Netanyahu told supporters, declaring victory even before final results were formally announced.
Netanyahu, 65, fought an all-out battle for a record fourth term against a spirited, united opposition based on a campaign revolving around no compromise attitude on Palestine's statehood.