The South Island Open Championships was a regional men's and women's grass court then later hard court tennis tournament founded in 1934 as the South Island Championships.
The tournament was played at other locations until 1978 when it was discontinued as part of the ILTF Independent Tour.
[1] This tournament has it origins in the Nelson Provincial Lawn Tennis Association Championships founded in 1899 that ran till 1910.
[1] The tournament was held in Nelson, but also other locations including, Christchurch, Timaru and Wānaka.
The North Island equivalent to this tournament was the North Island Open Championships also founded in 1932 by the Northern Lawn Tennis Association of New Zealand.