The K1 Fiance visa process from beginning to end should take about 6 to 9 months assuming that there are no errors in your paperwork and USCIS does not need additional evidence. In 2018 the typical wait time appears to be 8 months.
If there are errors in your paperwork, USCIS needs additional evidence, or there are other problems then the process can drag on for additional months or additional years. (I have seen this happen. A very intelligent potential client had been trying, unsuccessfully to bring his fiance to the United States for 3 years before meeting with me at my office. He just kept running into problems which caused his case to be delayed.) Therefore, it is very important that you submit all the paperwork required for your petition correctly.
Unlike other visa categories e.g. H1b, you cannot pay extra fees in order to receive faster (premium) processing of your case. The time period listed above can change. It is current for 2018.
Lawrence Gruner is a Sacramento Fiance Visa Attorney and a Sacramento Green Card Attorney with almost 20 years of experience. He handles Immigration cases throughout California, the United States and the World. He may be reached toll free at 888-801-6558 or at firstname.lastname@example.org
This article is general in nature and is just a basic introduction to this topic. You should always seek an experienced immigration attorney to review your specific facts and circumstances before proceeding with your case.