Plumbing invoicing software earns its place on one test: does the invoice leave the property with the technician, priced from the estimate the customer already approved, and does the money follow it the same day? An invoice that is written up in the office that evening from a wet carbon copy is where the small plumbing contractor loses parts that never got billed and labor that never got timed. The software's job is to make the invoice the natural end of the job rather than a separate chore.
Parts and labor on separate lines, always
A plumbing invoice is read by two people: the customer who wants to know what they paid for, and the accountant who needs materials and labor apart for cost of goods and for sales tax where it applies. Software that collapses a job into one line saves a minute on site and costs an hour at year end. The invoice tool on this site keeps parts, labor and any permit or disposal fee on their own lines and totals them the way an accountant expects to see them.
The price comes from the estimate, not from memory
Flat rate work should be invoiced at the flat rate that was shown and approved before the work started. The best invoicing software carries the approved estimate forward as the invoice with the line items intact, so the customer sees the number they said yes to. Anything that asks the technician to re-key the price at the end of a long job introduces the rounding that customers notice and dispute.
Payment on site is the feature that pays for the software
The difference between an invoice paid at the door and one paid after a reminder is the whole cash position of a small shop. Invoicing software that takes a card or a bank payment on the technician's phone and marks the invoice paid in the same record removes the reminder cycle. Where a customer must be billed later, the same record should send the reminder without the office writing it.
Keep the record the way the IRS expects
The Internal Revenue Service asks a business to keep records that support income, deductions and credits, and invoices are the primary support for income. A system that stores every invoice with its line items, its payment and its customer is doing the recordkeeping for you; a photo of a paper invoice is not. The IRS recordkeeping guidance is cited below and is worth reading once, because it decides what the software must retain rather than what is convenient.
Questions people ask about plumbing invoicing software
Can I invoice from the truck without a subscription?
Yes. The free invoice tool on this site builds a plumbing invoice with parts and labor on separate lines and prints or saves it. The paid product adds the saved customer and job records the invoice attaches to.
Should the invoice show the flat rate or the hours?
Show what the customer agreed to. If the job was quoted flat rate, invoice the flat rate; showing hours invites a negotiation about how long the job took after it is finished. Keep the hours in the job record for your own costing.
How long should I keep plumbing invoices?
Follow the IRS recordkeeping guidance for your situation and your accountant's advice. Invoicing software that never deletes a paid invoice makes the question moot; make sure you can export them if you ever leave the product.