Some unmarried South Koreans do not plan on revealing their entire fortune to their soon-to-be spouses, a recent survey by a matchmaking firm showed Tuesday.

According to the survey by Gayeon conducted on 250 unmarried men and 250 unmarried women between 25-39 years of age, 15 percent of respondents said they would not disclose 100 percent of their assets.

The most popular reason (49.3 percent) was "even spouses need some secrets," followed by "I might need emergency funds only for myself (30.7 percent), and I'm worried my assets would be too small compared to theirs (13.3 percent)."

In a separate question for all surveyed about the range of assets that should be disclosed -- multiple answers allowed -- 51.4 percent picked cash and bank balance, 47.2 percent said amount of debt, 28.2 percent said owned property, 24.8 percent picked owned stocks and 9.8 percent said expected inheritance.

When asked when they should reveal their assets to their partners, 37.4 percent said the conversation should occur when negotiating specifics about the marriage. Some 29.3 percent said it should be at any point during the romantic relationship, and 27 percent said such conversations should happen once marriage is being considered.