The Wii Shop Channel will close at some point in 2019, bringing an end to a service that launched in December 2006.

Nintendo has not set a specific date for the closing yet, but as of 21:00 (UK time) on March 26th 2018 you will no longer be able to add points to the Wii Shop Channel.  As of January 31st 2019 06:00 (UK time) you will not be able to purchase WiiWare, Virtual Console software and Wii Channels (including free ones) from the Wii Shop Channel.

This also affects the Wii Shop Channel accessed via the Wii U's backwards compatibility. 

Nintendo has promised to give an exact date of closure some point in the future, but if you were still planning to download software on the Wii Shop Channel you have just over a year left to do so.