The simple explanation would be both FICO as well as Vantage are credit scores which are on a scale for lenders to determine whether the individual is a risky borrower or not. Higher the scores, less risky the individual. The base scoring scale is similar for both which ranges from 300 to 850.
It is often discussed online which credit score should one focus on. FICO or Vantage? A host of ideas are presented like FICO is the one that is used majorly by the banks when making decisions, so focus on FICO. While this is true to a degree, one should focus on their credit habits because both FICO and Vantage scores require the same behavior for good scores. Responsible management of your credit will give you good credit scores for both Vantage and FICO. However, both of these have different models and therefore different weights are given to each factor, which is what causes the difference in the two scores most of the time.
The major difference between these two agencies is that FICO creates a specific model for each bureau whereas Vantage has a single tri bureau model. The bureaus here refer to the 3 major credit bureaus which provide the credit report and those are Experian, Equifax and Transunion. When you make an application to the lender, the lender accesses your credit report through any or all the three bureaus, which in turn will provide the credit report to the lender (FICO or Vantage). The bank then reviews the details of the report and uses their internal scoring to determine whether you would be approved or denied for the application.
The major question is whether there would be enough difference between the two scores to cause a difference in the decisions from the lenders. Most of the times, it wouldn’t. That’s because the lenders have their own criteria for decision making and regardless of what weights are given to each factor, the lenders are more likely to have their own recalculation. However, in some cases where it can make a difference is where a certain type of account is not reported. In those scenarios, those accounts would not feature in the calculation at all. For example, FICO 9 model ignores paid medical collections. Those no longer appear on the credit report. Vantage 3.0 and Vantage 4.0 models also ignore paid medical collections in the scoring, but the account may still appear on the report. There are other differences between the two models like treating all inquiries within a certain period as 1 inquiry. Recent FICO models have this window at 45 days while Vantage has this window at 14 days.
Overall, one should note that even though the scores might be different from the two agencies, they are still governed by the same principles which is how credit worthy an individual is. Therefore, as long as you focus on good credit habits like using your credit, paying on time, maintaining low credit utilization, no delinquencies etc, your credit scores are going to be good for the most part, regardless of which agency you check your scores from.