Manual expense reports, blurry receipts, approvals stuck in a manager’s inbox while they’re on annual leave, and a finance team re-keying every figure into Xero by hand. If that sounds like your month-end, the off-the-shelf tools haven’t fixed it. Most generic apps ask you to bend your process around their software, and the per-user fee keeps climbing every time you hire, whether you use half the features or not.
Companies usually start looking for something better at a recognisable moment: spreadsheets stopped coping, an audit flagged weak approval evidence, the per-user bill jumped after a round of hiring, or a corporate card rollout left card statements and expense claims that won’t reconcile. Whatever the trigger, the software’s assumptions don’t match how your business spends and signs off money.
I build expense management software to fit how your business runs, from the receipt on a phone to the posting in your ledger. It connects to the systems you already use, and you own it outright. No per-user pricing, no multi-year contract, no annual renewal surprise. This page covers where generic tools fall short, what I build instead, how a project runs, and roughly what it costs.
Where off-the-shelf expense tools fall short
For a small team with simple sign-off, the mainstream apps are fine. The trouble starts as a business grows past that:
- Per-user pricing has a cliff. A monthly fee per head looks cheap at 30 staff and uncomfortable at 200, and vendors often charge separately for API access, long-term receipt storage, premium support and onboarding.
- The features you need sit behind a higher tier. Cost-centre hierarchies, budget tracking and proper approval rules are often locked into a “premium” plan.
- Approval routing is too rigid. Most platforms handle “manager, then finance” well and struggle with anything past it: conditional thresholds, “this category always needs a director”, matrix sign-off, delegation when an approver is away, or rules that stop a salesperson approving their own travel.
- OCR isn’t as clean as the demo. Receipt scanning is excellent on a flat, well-lit receipt and noticeably worse on a crumpled or faded one, so someone still corrects merchant, date and VAT by hand.
- The “integration” is a CSV export. Plenty of platforms advertise an accounting integration that turns out to be a file someone downloads and imports. Categories rarely map cleanly to your nominal codes, and finance chases mismatches between the expense tool, the bank feed and the ledger.
- UK rules are an afterthought. Many of the best-known platforms are US-built, store data in the US, and treat HMRC mileage rates, VAT handling and Making Tax Digital as configuration rather than design.
- Contracts and cards lock you in. Enterprise tools typically want a two-to-three year commitment, and card-first platforms tie you to their corporate card.
The result is workarounds, reimbursements that drag on for weeks, and month-end reports nobody fully trusts. The subscription is rarely the biggest cost. The lost time and the errors are.
What I build instead
Built around your process
I map your approval hierarchies, spending policies, cost-centre structure and reporting needs before anyone writes code. Conditional routing, matrix sign-off, delegation cover for absent approvers, escalation when nothing is approved within a set window: the workflow matches your org chart, not the other way round.
No per-user fee
You pay a fixed price for the build and own the source code and the data. Your headcount grows; your software cost doesn’t follow it.
Connects to what you already run
Payroll and HR systems supply employee, manager and cost-centre data, so nobody maintains a second staff list. Legacy ERP or finance systems that no SaaS connector touches can be connected too. Accounting gets its own section below, because that’s where most expense tools fall down.
UK rules handled by design
Statutory HMRC mileage rates, VAT identification and split receipts, Making Tax Digital and an immutable audit trail, built in from the start. UK data residency where you need it.
Only the screens you use
Claimants see the few fields that matter for their workflow, which is usually what drives adoption in the first place.
Room to grow
Per-diem rules, project allocation or a new integration next year get added to the system you already have. No migration, no re-platforming, no waiting on a vendor roadmap.
Accounting integration: posting, not exporting
The expense system reads your chart of accounts, tracking categories, VAT rates and cost centres from Xero, QuickBooks Online or Sage, so the options a claimant picks are the ones your ledger uses. Nobody maps “Travel - UK” to a nominal code by hand at month-end.
When a claim is approved, it posts to the ledger automatically: a bill against the employee, or a journal, depending on how your accountant wants it. Each line carries its nominal code, VAT rate, cost centre and project, and a receipt without a valid VAT number posts with no VAT reclaimed. When the payment run goes, the reimbursement is marked paid in both systems.
Corporate card transactions come in from the card feed and are matched to the receipt and claim behind them. Finance sees the card statement, the expense system and the bank feed agree, with anything unmatched listed as an exception. Because the sync runs both ways, a code changed in the accounts package shows up in the expense system the same day, and the digital link from receipt to VAT return is unbroken for Making Tax Digital.
Features and modules
Every project is a bit different, but these are the parts that usually go in:
- Mobile receipt capture. Staff photograph a receipt and submit the claim from their phone, or email it in. Nothing piles up in a shoebox until month-end.
- Receipt OCR. Merchant, date, amount and VAT pulled off the image automatically, with a confidence score so finance knows which scans to double-check rather than reviewing every one.
- Policy checks. Submissions that break your spending rules (a missing receipt, an over-limit meal, a missing project tag) get flagged at the point of entry rather than discovered weeks later.
- Approval workflows. Routing by amount, category, department, cost centre or project code, with conditional thresholds, delegation cover and escalation built around how your sign-off works.
- Accounting sync. Two-way posting to Xero, QuickBooks Online and Sage, as described above.
- Mileage tracking. Distance calculated at HMRC statutory rates, with optional GPS logging and consent recorded at onboarding.
- Corporate card reconciliation. Card transactions matched automatically against submitted claims, with unmatched items flagged for follow-up.
- Cost-centre and project allocation. Spend tracked against budgets, including splitting a single claim across more than one project or cost centre.
- Reporting and dashboards. Spend by department, project, person or supplier, budget versus actual, and approval cycle times, with drill-down to the individual receipt.
- Reimbursement processing. Batch-approve claims and trigger payment, with clear status for each employee on what’s submitted, approved and paid.
- Multi-currency. Conversion and reporting for expenses incurred abroad, with the right VAT treatment for international claims and rates handled so the figures reconcile.
- Audit trail and access control. An immutable log of who submitted, approved, returned and paid each claim, role-based permissions, encryption in transit and at rest, and UK data residency where required.
How a project runs
I build in phases so you get something working early rather than waiting for everything at once.
First Gear (5 days)
A kickoff with your finance team, approvers and a few claimants to document your expense policy, your approval hierarchy, your cost-centre and nominal code structure, and the things that currently annoy everyone. I also pin down what has to integrate, since that’s usually the part that drives timeline and cost. You come away with a working prototype and a build plan with a fixed price.
First release
The core that earns its keep on day one: receipt capture and OCR, the approval workflow, accounting posting, reimbursement and basic reporting. A pilot with one team or department comes before a wider rollout, so issues surface at small scale.
Later phases (about a month each)
The pieces that aren’t needed on launch day: mileage tracking, corporate card reconciliation, advanced approval rules, budget alerts, custom dashboards and any further integrations. Splitting these out keeps the first release on schedule and lets you spread the spend.
Testing, deployment and migration
User acceptance testing, then go-live. Data migration is usually light (the employee and cost-centre list and the current nominal code mapping), though moving historical claims off a legacy system takes longer. Your old process keeps running until the new one is proven.
Training and support
Separate sessions for claimants, approvers and finance, plus documentation. After launch there’s a 30-day fix guarantee and the first month of hosting free, then an optional monthly plan.
A focused first release goes live within a month; mileage, card reconciliation and reporting follow in monthly phases. You get a progress update every week.
Cost and ownership
Custom development is a larger cost upfront than a subscription, and a much smaller one after that:
- Most builds cost £2k-£10k and go live within a month, with the price fixed at the end of First Gear. After launch you pay a flat monthly plan or host it yourself. SaaS is a per-user fee that rises every time you hire, before any setup fees, premium-tier upgrades or per-integration charges.
- The crossover point depends on headcount and feature scope. Below roughly 50 staff with simple sign-off, SaaS is usually the cheaper and more sensible choice. For larger teams, or where you need complex approvals, project allocation or legacy integration, custom tends to come out ahead over a three-to-five year horizon.
- You own the source code and the data, so there’s no vendor lock-in, no two-or-three year contract, and no surprise renewal price. If you ever want to take the work in-house or to another developer, you can.
A custom build isn’t right for everyone. Tell me your headcount and what you spend on expense software now, and I’ll tell you plainly if a subscription is the better answer for where you are.
Sector use cases
The data entities are similar everywhere (employees, expenses, receipts, approvals, cost centres, mileage logs, an audit trail), but the workflow on top of them changes a lot by sector. A few examples:
- Construction. Field teams submit material, fuel and plant costs from multiple job sites. Each claim is tagged to a job-site code, allocated to the project cost centre, checked against the purchase order, and posted to the project ledger, so site managers see budget versus actual without waiting for month-end.
- Healthcare. Mobile clinicians travel between patient sites and need mileage logged at HMRC rates with the audit-ready trail an NHS trust or CQC inspection expects. Per-diem rules vary by location and overnight stays, and approval can route through a clinical lead.
- Legal and accountancy practices. Billable expenses are matched to a client and matter code, checked for billability, and flow through to the billing module for the client invoice, removing the manual hop between time-tracking, expenses and billing.
- Manufacturing and supply chain. Procurement spend, freight, supplier visits and trade shows are matched against purchase orders, with three-way matching of PO, receipt and invoice, and spend analysed by supplier and product category.
- Charities and nonprofits. Spend is allocated to grant and restricted-fund codes, approvers confirm grant-rule compliance, and donor reporting comes straight out of the system rather than being assembled by hand.
- Professional services and consulting. Project-level expense tracking tied to client recharges and timesheets, so what gets billed back to the client is accurate and traceable.
- Field services. Mobile-first capture for technicians, including reliable submission when they’re working somewhere with poor signal.
Whatever the sector, the compliance rules, the terminology and the workflow get built in from the start rather than worked around afterwards.
Common Questions About Custom Expense Management Software
When does a custom build make more sense than Expensify, Zoho or Concur? ›
Per-user SaaS works well below roughly 50 staff with a single currency and a simple manager-then-finance sign-off. A custom build earns its place when the per-user fee starts to scale painfully, when your approval routing is complex (cost-centre sign-off, conditional thresholds, delegation), when you need to allocate spend to projects or grants, or when you have to integrate with a legacy ERP or HR system that no SaaS connector covers. If SaaS is the better call for you, I'll say so.
Is there a difference between expense tracking, expense reporting and expense management software? ›
Mostly in emphasis. Tracking means capturing receipts and spend, reporting means turning claims into reports for approval and month-end, and management covers the whole path from receipt to approval, posting and reimbursement. A custom system covers all three, sized to the parts your business needs.
How does custom development cost compare to SaaS? ›
A custom build is a larger cost upfront and a small one after that, a flat monthly plan or your own hosting, while SaaS is a per-user fee that rises every time you hire. The crossover point depends on headcount and feature scope, but for larger teams or feature-heavy requirements custom usually wins over a three-to-five year horizon.
What's the typical development timeline? ›
A focused first release covering receipt capture, approvals and accounting posting usually goes live within a month. Mileage, corporate card reconciliation, advanced approval rules and reporting follow as later phases of about a month, each at a fixed price. You get the price and go-live date in the build plan at the end of First Gear, the 5-day prototype stage, and a progress update every week.
Which accounting and HR systems can it integrate with? ›
Xero, QuickBooks Online and Sage are the usual ones. Approved claims post straight to the right nominal code with the VAT rate, cost centre and project attached, and reimbursements are marked paid when the payment run goes. HR or payroll systems supply employee, cost-centre and manager data, and corporate card feeds and legacy ERP or finance systems outside the usual connector lists can be connected too.
Will it handle HMRC and UK compliance? ›
It's built for UK finance teams. That means statutory mileage rates (45p per mile for the first 10,000 business miles, 25p after), VAT identification and split receipts so VAT returns reconcile, digital records for Making Tax Digital, and an immutable audit trail that records who submitted, approved and paid every claim. Receipt images and approval records can be retained for the six years HMRC expects, with GDPR-compliant handling and UK data residency.
How do you handle updates and changes? ›
You own the source code, so there is no vendor lock-in and no forced upgrade. Optional monthly plans cover changes and new features, but you're also free to make changes in-house or bring in another developer. A new policy rule, expense category or integration is usually a small piece of work, not a wait on someone else's roadmap.
Do you provide training for our team? ›
Yes. Each group is trained separately, since their needs differ: claimants need around an hour on capturing and submitting receipts, approvers need a couple of hours on routing and policy checks, and the finance team needs longer on administration, ledger posting and month-end. Documentation is included.