Are Your London Projects Really Profitable? The Job Costing Numbers Every Builder And Tradesperson Should Track
- bes Accountancy Services
- Jun 14
- 7 min read
For many builders and tradespeople in London, the biggest financial challenge is not getting work. It is knowing whether each job is actually making money.
A project can look successful when invoices are going out, labour is busy, and materials are moving through site. But once labour time, subcontractors, materials, travel, VAT, CIS, delays, variations, admin, and overheads are included, the real profit can look very different.
At Bes Accountancy, we believe construction firms should not have to wait until year end to find out whether their projects were profitable. Founded in 2020, Bes Accountancy is a leading London based accounting company serving businesses of all sizes and self employed professionals across the UK. Led by Besnik Vata, a certified bookkeeper with an AAT license, our dedicated team of five specialists helps businesses streamline their finances, stay compliant, and make better commercial decisions.
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Why Job Costing Matters For London Construction Businesses
Construction and trade businesses often work with tight margins, moving deadlines, changing material prices, subcontractor payments, and client variations. That is why job costing is not just an accounting task. It is a profit protection system.
A busy diary can hide weak margins. A high value project can create pressure if labour runs over, supplier invoices arrive late, or variations are not priced correctly. In London, this becomes even more important because parking, travel, waste disposal, congestion costs, site access, and subcontractor availability can all affect the final result.
Job costing helps builders and tradespeople understand which jobs are actually profitable, which services are underpriced, where labour time is being lost, whether materials are being estimated properly, whether subcontractor costs are being controlled, and whether each project contributes enough towards business overheads.
“Many builders know their trade extremely well, but they do not always have clear visibility over job by job profit. That visibility is what turns hard work into a stronger business,”
says Besnik Vata, director of Bes Accountancy, a London based accounting company.
learn more about BES Accountancy on our About Us page
Want to dive deeper into accounting for businesses?
Read our related blog, where we provide a full guide to submitting your File Your Tax Return Early.
The Key Numbers Builders Should Track
A profitable construction business needs job level visibility. It is not enough to know total income and total expenses. Builders and tradespeople need to understand how each job performs on its own.
The most important figures include labour costs, materials, subcontractors, plant and equipment hire, travel, parking, waste disposal, insurance, admin time, software, management time, and general overheads. These figures help compare the quoted cost against the actual cost, showing whether the job made real profit or simply kept the team busy.
Labour should include employee hours, overtime, subcontractor time, site preparation, supervision, corrections, and travel where relevant. Materials should include the main materials, smaller consumables, delivery charges, wastage, emergency purchases, and returned items. Subcontractor costs should be reviewed carefully, especially where CIS applies, because payment timing, deductions, and monthly records can affect both compliance and cash flow.
Many builders focus on what is left after paying labour and materials. That is useful, but it is not the full picture. Gross profit usually looks at sales value, direct labour, materials, subcontractors, and direct project costs. Net profit goes further by including admin, insurance, accounting, software, vehicles, marketing, management time, finance costs, and general business overheads.
This matters because a job can look profitable at gross level but still be weak after overheads. Smaller jobs may sometimes deliver better margins than larger projects. Clear reporting helps builders decide which work to accept, reject, or reprice.
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Why Clean Bookkeeping Comes First
Job costing only works when bookkeeping is accurate. If records are late, unclear, or mixed between jobs, it becomes difficult to know which costs belong to which project.
Clean bookkeeping helps construction businesses allocate supplier invoices correctly, track subcontractor payments, separate personal and business expenses, monitor cash flow, review profit before the job ends, and prepare better management accounts. It also reduces stress around VAT, payroll, CIS, and year end accounts.
This is where Bes Accountancy supports construction and trades clients with practical financial systems. BES provides a full suite of accountancy services, including bookkeeping, payroll management, VAT returns, financial accounting, and account preparation for sole traders and partnerships. Our expertise in Xero and QuickBooks helps clients maintain accurate, efficient, and accessible financial records.
The strongest construction businesses do not treat bookkeeping as basic admin. They use it as a management tool. When records are clean, owners can quote better, control costs earlier, chase payments faster, and understand which jobs deserve more attention.
VAT, payroll, and CIS also affect project profitability. Builders need to know whether quotes are VAT inclusive or VAT exclusive, whether input VAT is being reclaimed properly, whether payroll costs are correctly allocated, and whether CIS deductions and monthly returns are being handled correctly.
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Common Job Costing Mistakes Builders Make
Many construction and trades businesses work hard but lose profit through avoidable mistakes. The most common issue is quoting from memory instead of using real cost data from past projects.
Other common mistakes include failing to track labour hours properly, forgetting smaller materials and consumables, not charging correctly for variations, absorbing extra work to keep the client happy, mixing costs from different jobs, recording supplier invoices too late, ignoring overheads when pricing, and treating turnover as the main success measure.
In our view, turnover can be misleading. A construction company can appear to be growing while profit quality is getting weaker. That is why business owners need regular financial information, not just year end accounts.
“Most construction profit problems are not discovered when the quote is written. They are discovered when the job is finished and the records finally catch up,”
says Besnik Vata, director of Bes Accountancy, a London based accounting company.
How Bes Accountancy Helps Construction And Trades Clients
Bes Accountancy is built around three core values, Availability, Efficiency, and Trust. These values matter because construction businesses often need timely answers, practical reporting, and reliable support when deadlines are tight.
We support builders, electricians, plumbers, decorators, carpenters, flooring contractors, roofers, refurbishment companies, extension specialists, sole traders, subcontractors, and small construction firms. Our services include bookkeeping, VAT returns, payroll management, CIS support, financial accounting, account preparation for sole traders and partnerships, Xero and QuickBooks support, management reporting, cash flow visibility, and job costing guidance.
This support gives business owners more control over their finances. Instead of guessing whether a job has gone well, they can review the numbers and make decisions based on evidence.
A practical example is simple. One builder has busy projects but records supplier invoices late, estimates labour from memory, tracks variations through messages, and reviews VAT and CIS close to the deadline. Another builder updates bookkeeping regularly, tracks materials by job, records labour properly, allocates subcontractor costs, and reviews reports before each job finishes.
Both may look busy. Only one has the numbers needed to protect profit and make better decisions.
Final Thoughts
Bes Accountancy is a leading London based accounting company serving clients across the UK, with a strong focus on helping small and medium sized businesses stay compliant, organised, and financially informed.
For builders and tradespeople, job costing is not just an accounting exercise. It is a way to protect profit, price work properly, control cash flow, and build a stronger construction business.
If your projects are busy but your profit feels unclear, now is the time to review the numbers behind each job.
To explore more about Bes Accountancy, refer to our About Us page, Instagram page, Projects section, and other blog articles.
Speak to a qualified accountant for tailored advice.
Call for a free quote: 07816264205 | Email for a free quote: Info@bestax.co.uk
About BES Accountancy
Founded in 2020, BES Accountancy is a London based firm providing expert financial services to businesses of all sizes and self employed professionals across the UK.
Led by Besnik Vata, a certified bookkeeper with an AAT licence, our dedicated team of five specialists offers tailored support designed to help businesses stay compliant, improve visibility and grow with confidence.
Our services include bookkeeping, financial accounting, VAT returns, payroll and account preparation for sole traders and partnerships. We also support clients with Xero and QuickBooks, helping them build more accurate and efficient digital systems.
At BES Accountancy, our work is shaped by three core values, availability, efficiency and trust.
Get a free quote by phone | Email Info@bestax.co.uk
FAQ:
What is job costing for builders?
Job costing is the process of tracking the income, labour, materials, subcontractors, equipment, overheads, and other costs linked to each construction project. It helps builders understand whether individual jobs are truly profitable.
Why is job costing important for tradespeople?
Job costing helps tradespeople avoid underpricing work, missing hidden costs, and relying only on turnover. It gives a clearer view of real profit after labour, materials, travel, equipment, VAT, CIS, and overheads.
Can Bes Accountancy help construction firms with CIS?
Yes. Bes Accountancy supports construction firms and trades clients with CIS, bookkeeping, payroll, VAT, and financial accounting, helping them keep cleaner records and stronger compliance systems.
What numbers should builders track on each project?
Builders should track labour, materials, subcontractors, equipment hire, travel, parking, waste disposal, variations, VAT, CIS, payroll costs, overheads, and final profit margin.
Does Bes Accountancy only work with London construction businesses?
No. Bes Accountancy is based in London and serves clients across the UK, although London remains a core client base and an important part of the firm’s positioning.
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