Nationals from Maldives and Singapore can enter visa and without an ETA/Visa.

Everyone else can apply for an ETA (Electronic Travel Authorization) prior to arriving. The ETA costs US$10 for SAARC countries and US$20 for everyone else.

Sri Lankan visas can be extended for up to three months without much difficulty.

ETA Sri Lanka

Emabssies and Consulates, Foreign and Sri Lankan.