Way back in the day, the scoring models used the "high balance" field in place of a credit limit, for charge cards. High Balance was simply the highest your balance had ever gone. Thus, if the highest your balance had ever gone was $1032, then the model would calculate your utilization as if the charge card were a credit card with a $1032 credit limit.
Now the scoring models (at least FICO 8 and 9) no longer do that. Instead they leave charge cards out of the utilization calculation altogether. The following is a hekpful overview of it:
https://thepointsguy.com/2016/07/how-charge-cards-affect-score/
What is unclear to me is whether old models still use the old system of High Balance = Credit Limit. In particular, does FICO 98 and FICO 04 (models released in 1998 and 2004) still use this older system? It matters since the mortgage industry uses FICO 98 for Experian and FICO 04 for TU and EQ.
If you aren't looking to buy a house then I can't imagine that last caveat mattering. Someone like Thomas Thumb, who knows a good deal about charge cards, may know the answer to how the mortgage models work today.
