The next step was another 9 submarines of HDW type 214 built in Korea and delivered in 2006-2020. These are considerably larger and have fuel cells for extended underwater operation without the need to snorkel to recharge batteries.
The final class of boats in the current ROKN program is the KSS-III type submarine designed and built domestically and entering service starting in 2021. Again, 9 boats are planned and 4 are already in service. While still relying on Diesel-electric propulsion with air-independent fuel cell power for extended underwater operations, the traditional lead-acid batteries have been replaced by Lithium-ion in the 4th and subsequent boats. The KSS-III submarines also feature vertical launch tubes for land attack missiles.
There has been some interest in buying Korean submarines by other countries. Both Canada and the Philippines have shown interest. (If the Philippines does buy a couple of submarines, they would be the first operated by that nation.)
