A homeowner discovers in year four that work done in year one was never done correctly. A customer notices a charge that has been recurring since a service was cancelled. A business realizes that an invoice from two years ago was never paid.
In each case the first question anyone competent will ask is not what happened. It is when, and whether the window is still open. Several windows exist at once, they are set by different parties, and the shortest one is frequently the one nobody was told about.
The deadline set by law
A statute of limitations is the period during which a claim can be brought at all. After it expires the claim generally cannot be pursued regardless of how strong it is, which is a hard thing to hear and is the point of the rule: evidence degrades, witnesses move, and the system declines to adjudicate very old disputes.
The periods vary by state and by the type of claim, and the variation is substantial. A written contract, an oral agreement, property damage, personal injury, and a defective construction claim can each carry a different period in the same state. Some states also apply a separate outer limit for construction defects measured from completion rather than from discovery, which can close a door even where the problem was genuinely hidden.
The practical instruction is simple: find out the number that applies to your kind of claim in your state early, and treat the real deadline as several months before it. Filing on the last available day is how people discover the period was shorter than they thought.
The deadlines set by a contract
Frequently much shorter than the legal ones, and enforceable. Contracts routinely require notice of a problem within a set number of days, sometimes as few as ten or thirty, and provide that a claim not raised in that window is waived.
Warranty windows work the same way. A one year workmanship warranty means one year, and a complaint raised at fourteen months is outside it even though the work was clearly defective. Manufacturer warranties on materials often run longer than the installer's warranty on labor, which is why a failure can be half covered.
Insurance policies carry their own. Prompt notice of a loss is a condition of nearly every policy, and some contain a shortened period for bringing suit against the insurer, considerably briefer than the state's general limit for contract claims.
Read the notice provisions of anything you sign at the moment you sign it, and write the deadlines somewhere you will see them.
The deadlines set by a company
The shortest of all, and the ones most encountered in ordinary life. Return windows. The period for disputing a charge with a card issuer, which is defined by law and is not long. The window for appealing a denied insurance claim or a denied benefit. The time limit on a warranty registration.
These are usually recoverable if missed, in the sense that other routes remain, but the company route is by far the cheapest and the fastest. Missing it does not end the matter and it does convert a phone call into a process.
When the clock actually starts
The most argued question in this whole area. The general rule is that the period runs from when the claim arose, meaning when the harm occurred or the contract was breached.
Many states apply some form of discovery rule for problems that could not reasonably have been found, so that the clock starts when the problem was discovered or should have been discovered. That is what makes hidden defects claimable years later. It is also why the phrase should have been discovered does so much work: an owner who noticed a stain in year two and did nothing may be treated as having discovered it then.
The lesson is that noticing something and doing nothing about it can start a clock you did not know you had started. Writing down the date you first noticed a problem, at the time, is one of the more valuable ten second habits available.
What to do when a deadline is close
Two things, in order. Get advice immediately rather than doing more investigation, because the deadline does not pause while you gather evidence and an attorney can usually tell you the applicable period in a short conversation.
And put the other side on notice in writing, dated, describing the problem. That does not stop most statutory clocks, but it satisfies most contractual notice provisions, and those are the ones most often missed. A short factual letter sent today costs nothing and preserves an option.
The two habits that keep you inside all of them
Date everything as it happens. The day you first noticed, the day you first reported it, the day they said they would come back. A running note in a single file, kept from the beginning, makes every question in this piece answerable.
And read the notice section of contracts before there is a problem, then write the two or three deadlines on the front page in pen. Almost nobody does this, and the people who do are never the ones discovering in month eleven that they had thirty days.