First time fix is the share of jobs completed on the first visit, and it is the most useful single number a service business can track, because almost every other problem shows up in it. Parts stocking, diagnosis quality, scheduling accuracy and technician skill all move it, and a business that improves it improves capacity, cost and reputation simultaneously.
What a second visit actually costs
On the worked example this site publishes, a technician completes 5.2 jobs a day and a job invoices $285. A repair that takes two visits consumes two slots and produces one invoice, so every ten percentage points of first time fix is a measurable amount of capacity handed back to the business without hiring anybody.
Measure it honestly or not at all
The temptation is to exclude the visits where a part was never going to be on the van. Do not: the point of the measure is to show what your customers experience, and they do not care why. Track the reasons separately, as parts, diagnosis or access, and improve the reasons rather than adjusting the definition.
The three levers, in order
Van stock for the parts that are most often the answer, which your own job history can identify. Better information at booking, so the technician arrives knowing what the fault probably is. And enough time in the slot, because a job rushed to fit the schedule is a job that comes back.
Where the best practice lists come from
Almost every field service management best practice worth following is a way of moving this number: capture the fault properly at booking, record what was done, review recurring faults, keep the schedule honest. A practice that does not eventually show up in first time fix is probably a habit rather than a practice.
Questions people ask about first time fix
What is a good first time fix rate?
It varies too much by trade for a number here to be useful. What matters is your own trend and the reasons behind the failures.
How do we track it without new software?
Count return visits against the same fault. If your work orders name the fault, this is a report rather than a project.
Does van stock always help?
Only for the parts that are actually the answer often enough. Your own job history tells you which; guessing produces expensive vans.