Essentially a K3 visa was designed as a fast alternative to the immigrant visas (IR1/CR1). K3’s are a non-immigrant visa so one cannot stay indefinitely in the United States on one of these visas. For the Thai/American couple looking to immigrate to the USA, the K-3 is a good choice if time is of the essence.
The K-3 generally takes about 8 months where the immigrant visas take about one year from submission of visa application to obtainment of the visa. What this means is that you can shave 4 month off of the time it will take you to get your Thai wife into the US.
OTHER ASPECTS OF THE K-3 SPOUSE VISA FROM THAILAND
The K-3 Visa is a two year visa so, unlike a K1 fiancée visa, your Thai spouse will have plenty of time to obtain a green card. The K-3 visa is also a multiple reentry visa so your Thai wife can come and go from the country without having to worry that her visa will be revoked. A Thai spouse can also obtain a work permit on the K3 visa so that she can get a job.
The only major downside to a K-3 visa for a Thai wife is that she doesn’t enter the United States as a permanent resident. On an IR-1 or a CR-1 the Thai spouse would come into the US as a permanent resident (green card holder), but with a K-3 it is a non-immigrant category so she will have to adjust status once in the United States (for more on IR-1 and CR-1 Visas for a Thai spouse. The work of obtaining permanent residence in the US is “back-loaded,” with the K-3 Visa and essentially put off until arrival in the United States, but with the 2 year duration of the K-3 visa the pace for obtaining a green card for your Thai husband or wife can be more leisurely than with other visas.