Universal basic income (UBI) is a social welfare proposal in which all citizens of a given population regularly receive a minimum income in the form of an unconditional transfer payment, i.e., without a means test or need to perform work. In contrast, a guaranteed minimum income is paid only to those who do not already receive an income that is enough to live on. A UBI would be received independently of any other income. If the level is sufficient to meet a person's basic needs, it is considered a full basic income; if it is less than that amount, it is called a partial basic income. As of 2025, no country has implemented a full UBI system, but two countries—Mongolia and Iran—have had a partial UBI in the past. There have been numerous pilot projects, and the idea is discussed in many countries. Some have labelled UBI as utopian due to its historical origin.