How the Visa Bulletin works
US law caps how many family-sponsored and employment-based green cards can be issued each year, and limits how many can go to natives of any single country. When demand in a category exceeds those caps, a queue forms. The monthly Visa Bulletin, published by the Department of State, is the official record of that queue: it lists cut-off dates for every preference category and country of chargeability. Your place in line is your priority date, and you move forward as the cut-off dates advance. This tracker lets you compare your priority date against the cut-off so you can see at a glance whether you are current.
Reading the charts correctly
The bulletin contains two sets of charts. Final Action Dates show when your green card can actually be granted - when your priority date is earlier than this date, a visa number is available to you. Dates for Filing show when you may submit your application paperwork, which is usually a little earlier and lets you get documents into the system sooner. Each month, USCIS states which of the two charts applies for adjustment-of-status filings, so always confirm that before relying on a date. A 'C' means the category is current with no wait, while 'U' means unavailable.
Why your country of chargeability matters
You are charged to your country of birth, not your nationality. Because a handful of high-demand countries - notably India, China, Mexico and the Philippines - generate far more applicants than the per-country limit allows, their cut-off dates can lag years or even decades behind the worldwide column. If you were born in a lower-demand country your wait may be minimal in the same category. In some cases a married couple can use cross-chargeability to claim the spouse's more favourable country of birth, which is worth checking if your own country is heavily backlogged.
How to use your priority date wisely
Track the bulletin every month, because dates can jump forward, creep slowly, or even retrogress when demand surges. Note your exact priority date and keep the receipt notice that proves it, since that date governs your whole case. When the Dates for Filing chart reaches you, prepare and submit your paperwork promptly so you are ready the moment a visa number becomes available under Final Action Dates. Keep your documents, medical exam and affidavit of support current, and watch for category movement that might let you upgrade or transfer. If your category is badly backlogged, it is worth discussing alternative paths with an immigration attorney.
Remember that this tool uses illustrative dates for learning. The official monthly Visa Bulletin is the only authoritative source for real cut-off dates, so check the current edition before making any decision about filing.