How to check every job sheet before invoicing

To check every job sheet before invoicing, write down what a complete sheet holds for each type of job, check each one the day it comes back, and hold the invoice until the gaps are filled. Send anything missing to the engineer while they can still fix it. Your job system stays the record.

A job sheet that reads "Job complete", with no parts, photo or signature, is how an invoice comes back with a query instead of a payment. This post covers why sheets come back thin, what a complete one holds, and who checks it and when.

Why do engineers leave job sheets incomplete?

Because the sheet is written at the end of the job, by someone tired and already thinking about the next site. Most engineers care about the work; the sheet is just the last thing they do.

It is written at the worst moment. On a phone in the van at 18:00, after hours on the tools, detail that was obvious on site shrinks to a line.

The form was designed in the office. Questions that do not fit the job get "N/A". Make every field mandatory and the answers tick the box and say nothing; make the form shorter and the parts, the cause and the follow-on work go missing.

Nobody seems to read it. If an engineer never hears that a sheet was used, it feels like admin for its own sake.

The cost lands at the invoice. A client's accounts team that cannot see a signature, a photo or the certificate will query the invoice, and payment waits while someone goes back to the engineer. Business owners affected by late payment spend 86 hours a year on average chasing invoices, according to the government's response to its late payment consultation (opens in a new tab), updated on 24/07/2026, which also sets out a plan for a statutory time limit on raising invoice disputes. Whatever the deadline, a query is easiest to answer when the evidence is already on the job.

As a worked example, 25 engineers finishing 4 jobs a day send back 100 job sheets a day. If 8 have a gap and nobody looks until month end, there are about 160 to chase, each about a visit the engineer barely remembers.

What should a complete job sheet include?

Whether you call it a job sheet, a worksheet or a job card, a complete one explains the visit to the client, the office and the next engineer. As a job sheet template:

• Work done, in words the client can read: the fault, the cause and the fix.
• Times: arrival, departure and any break, so the hours billed can be checked.
• Parts and materials, so nothing is missed off the invoice.
• Readings and test results the job calls for.
• Photos before and after of the thing worked on.
• A signature, with the printed name of whoever signed.
• Follow-on work found, with a photo, so it can be quoted.
• Certificates the work requires, attached to the job.

Which jobs need a certificate?

Electrical work. An Electrical Installation Certificate covers a new installation, a new circuit or a replaced consumer unit or distribution board, and an addition or alteration without a new circuit may go on a Minor Electrical Installation Works Certificate, according to the notes on the IET's model Electrical Installation Certificate (opens in a new tab) for BS 7671:2018+A4:2026, dated 15/04/2026. The same notes say the certificate is valid only with its schedules of inspections, circuit details and test results attached.

Electrical inspections in rented homes. In England, a landlord must have the electrical installation inspected and tested at least every 5 years and give the tenant a copy of the report within 28 days, according to GOV.UK's guidance on electrical safety standards in rented homes (opens in a new tab), published on 01/11/2025. The report belongs on the job before it is invoiced.

A checklist by job type:

How do you check every job sheet before invoicing?

Give one person the check, every day, against the list for that job type.

Check the same day. A supervisor or service desk lead reads every sheet that came back, at a set time such as 16:30. A gap found today takes one message; at month end, a return visit or a guess.

Send the gap back while the engineer can fix it. A signature can only be got at the door, and a photo of a board only before the cover goes back on. Tell the engineer exactly what is missing and on which job, ideally before they leave site.

Hold the invoice, rather than send it to be queried. Raise invoices only for jobs whose sheet passed. List each held job with its reason and an owner, so held does not become forgotten. An invoice that arrives with its evidence gives the client's accounts team nothing to send back.

Track the reasons, then fix the form. Tally why sheets fail each week. If after photos keep going missing on PPM visits, make that a required answer on the PPM form alone. If a question is always "N/A", remove it. The aim is a form short enough to finish in the van and complete enough to invoice from.

Some things stay with a person: rewriting a note before the client sees it, deciding whether a client's email can stand in for a signature, and signing any certificate.

What do BigChange, Joblogic and Simpro already do?

All three capture photos and signatures on site. None decides whether a sheet is good enough for that client. Pages were read on 30/10/2026 unless dated.

BigChange

BigChange's proof of service page (opens in a new tab) describes time and location stamped photos before, during and after the work, and customer sign-off that reaches the office in time to raise the invoice. Its worksheets page (opens in a new tab) says engineers cannot mark a job complete until required risk assessments and safety forms are filled in. Someone still reads whether the answers make sense. See the BigChange integration.

Joblogic

Joblogic lets a form be made mandatory against a visit or an asset, according to its guide to assigning job forms (opens in a new tab), published on 30/04/2024, and its web release for the week of 15/09/2025 (opens in a new tab), published on 23/09/2025, added a setting that stops a visit being completed without a photo or attachment. Whether the photo shows the finished work is still a person's call. See the Joblogic integration.

Simpro

Simpro Mobile lets field staff record service reports, notes and photos, complete safety and compliance audits and capture customer signatures on job cards, then send the invoice once a job is complete, according to its mobile app page (opens in a new tab). Someone still compares the job card with what that client needs. See the Simpro integration.

Which way of checking job sheets suits you?

By eye, with a spreadsheet tally. A supervisor who knows the clients reads each sheet and logs why any fail. Nothing to set up, but it needs their time every day.

Required answers in the job system. The right place to start. It checks that something is there, not that it is right.

A general automation tool. It can flag a job closed with an empty field. Reading a note or judging a photo takes building and upkeep.

An AI agent. It reads each sheet against your standard, asks the engineer about gaps and holds the invoice. It needs your list written down, and a person approves anything the client will read.

How does Centrus help?

Centrus checks job sheets alongside BigChange, Joblogic or Simpro. Your job system stays the record.

• Gaps fixed at the door. When a job is completed, an agent in Agent Builder checks the worksheet for the signature, photos and readings your rules require, and tells the engineer on WhatsApp what is missing (missing signatures flagged on site).
• Checked before the client reads it. At 17:00 each weekday the day's worksheets are checked against your standard. Notes written for the van are rewritten for the client and held for a manager to approve, with the original kept on the job (worksheets checked).
• Invoices held for the paperwork. Jobs ready for invoicing are checked against your evidence rules. Clean ones are raised, and held ones are listed for the desk (invoices held for evidence).

Does this work at a real business?

BSML, a facilities management company of around 110 staff on BigChange, lists "job creation, worksheet processing, and proactive operational monitoring that alerts the right person before situations escalate" among the tasks its agents now handle, according to its case study. Its time figure covers every agent, not this check alone: "Across the suite deployed, over 100 hours of manual back office work alone is returned to the team every month."

Where next?

Photos sent on WhatsApp can be filed to the right job, certificates sent from the job, and the rest is on paperwork and compliance. To see your own job sheets checked before they are invoiced, Book a demo.

Frequently asked questions

What should be on a job sheet?

The work done in words the client can read, arrival and departure times, parts used, readings or test results, photos before and after, a signature with a printed name, any follow-on work, and the certificates the job requires. Keep a short list for each job type, so the engineer and the checker work to one standard.

Should you invoice before the job sheet is complete?

Usually not. A client who cannot see the signature, the photos or the certificate will query the invoice, and payment waits while someone chases the engineer. Hold the invoice with the reason written down, fix the gap, then send it complete, unless the client has agreed otherwise in writing.

Why do engineers avoid paperwork?

Mostly because it comes at the worst moment: in the van at the end of a long day, on a form designed in the office, for a result they rarely see. Shorter forms lose detail, and blanket mandatory fields invite box ticking. Ask only what each job type needs, and tell engineers when their sheets are used.

Can Centrus check job sheets in BigChange, Joblogic or Simpro?

Yes. When a job is completed, an agent checks the worksheet for the signature, photos and readings your rules require and tells the engineer on WhatsApp what is missing. At 17:00 each weekday the day's worksheets are checked against your standard. Your job system stays the record, and a manager approves any rewritten note.