Waiting is not what fixes it
Owners ask for a number because every consumer-credit article gives one. Business credit does not work that way: there is no cooling-off period written into anything, and no funder is counting the days since your last application.
What they are looking at is whether the thing that caused the decline is still true. Time only helps to the extent it changes that. Ninety days of the same statements changes nothing at all.
How long each reason actually takes
Negative balance days or overdrafts: about 60 days. Most funders read the last three to six months of deposits, so you need enough clean months to move the average. Two clean months against one bad one is usually the point where the file reads differently.
Low or inconsistent deposits: 60 to 90 days, and only if the deposits genuinely rise. This is the reason most likely to be misdiagnosed as bad luck when it is a seasonality pattern the funder can see and you can explain.
Time in business: whatever the calendar says. Most revenue-based funders want six months; many banks want two years. Nothing accelerates this.
Credit score: 30 to 90 days for a change of any size, longer if the issue is a judgment or collection rather than utilisation.
An existing advance or lien: as soon as the balance is low enough, which is a payoff question rather than a waiting question. Some funders will write a second position immediately.
Wrong product: zero days. If you were declined for an unsecured term loan on a purchase that is actually equipment, you are not waiting for anything — you were in the wrong queue.
Why applying again too early costs you
Each application can put an inquiry on the record and, with some funders, a UCC filing. Those are visible. A cluster of them inside a few weeks is the single clearest distress signal a small business file can send, and funders price it.
There is also a quieter cost. Some funders keep a declined file and will not look at the same business again for a set period regardless of what changed. Burning a good funder on a premature second attempt can put them out of reach for the application that would have worked.
The exception worth naming: applying to a genuinely different kind of funder is not reapplying. A bank decline followed by a revenue-based application the same week is two different questions asked of two different readers, not one question asked twice.