Replacing Excel Macro Workbooks with a Web App in London: Cost and Method

The verdict in three sentences

For a wine merchant in London that runs quotes, allocations and stock in an Excel workbook with VBA macros, replacing it with a custom web application costs roughly 25,000 to 60,000 GBP excluding VAT in 2026 with a UK agency, over 8 to 12 weeks. The real risk is not the file itself but dependence on a single person who understands the macros, plus version conflicts as soon as three people work in it at once. With 6 to 10 hours saved per week and data migration budgeted separately (2,000 to 5,000 GBP), payback usually lands between 18 and 40 months.

When a VBA workbook becomes a business risk

The macro workbook has often served well for ten years. It becomes a problem once it carries critical processes: pricing by vintage, en primeur allocations, stock in the warehouse and in bond. The warning signs are easy to spot.

If three of these signals are present, the question is no longer whether to replace the file but when and with what scope.

Cost of an Excel to web app migration in 2026

The ranges below are UK market estimates for 2026, for a business with 10 to 50 staff. They assume a browser-based application with user accounts and role-based permissions.

Two factors move the bill. The first is workbook quality: documented macros and clean tabs halve the audit. The second is the number of business rules hidden in formulas, for example an automatic discount above 60 cases or a different price per channel (independent merchants, on-trade, export).

For companies comparing with an offshore option, Kolonell builds this kind of business application from Dakar: a simple application costs 2,500,000 to 4,000,000 FCFA (3,810 to 6,100 EUR), a medium-complexity one 4,000,000 to 7,000,000 FCFA (6,100 to 10,670 EUR), with maintenance from 35,000 FCFA per month.

A four-step method so nothing gets lost

• Macro inventory: every button, named formula and tab is listed with its business rule in plain language. Allow 3 to 5 days.
• Data model: tabs become tables (customers, SKUs, vintages, stock, quotes) with unique identifiers, which removes duplicates.
• Development in releases: the quote module, used daily, ships first, then stock, then allocations. Each release is tested on real data.
• Parallel run: for 2 to 4 weeks Excel and the app run side by side, then the workbook becomes read-only.

The parallel run is often cut to save time. That is a mistake: it surfaces forgotten rules before they cost an order.

Mini case study

Illustrative scenario: James, finance director of a 22-person wine merchant in London, manages 1,800 SKUs in a VBA workbook written by a salesperson who has since retired. Three people each spend about 3 hours a week rekeying and checking, so 9 hours a week in total.

Budget: 42,000 GBP for the application plus 4,000 GBP for data migration, 46,000 GBP in all. Hosting and maintenance: 500 GBP per month.

Estimated gain: 8 hours a week over 46 weeks, so 368 hours a year. At a loaded cost of 60 GBP per hour, that is 22,080 GBP a year. Minus 6,000 GBP of annual maintenance, the net gain is 16,080 GBP a year. Payback comes at around 34 months on time saved alone, and much sooner if you count one pricing error avoided on an export order.

FAQ

Can we keep Excel for some uses?

Yes, and it is often advisable for one-off analysis. The app exports data to CSV or XLSX in one click, keeping Excel's flexibility without making it the source of truth. Allow 500 to 1,500 GBP for well-formatted exports.

How long will the team take to adopt the tool?

With 2 hours of training and a quote screen close to the old tab, people are comfortable within 1 to 2 weeks. Adoption rarely exceeds 80 % if the old file stays editable, which is why it should become read-only.

Should we buy an off-the-shelf wine trade system instead?

Specialist wine ERPs cost 70 to 220 GBP per user per month, plus 5,000 to 18,000 GBP of configuration. They suit standard processes. Custom software makes sense when your allocation or pricing rules are your commercial edge.

What if the macros contain errors?

The audit uncovers some in more than half of cases. The rule is fixed in the app and the difference documented, so a wrong calculation is not carried into the new tool.

Where should commercial data be hosted?

UK or EU hosting with daily backups kept for 30 days costs 40 to 150 GBP per month, which is enough for a business this size and keeps UK GDPR compliance simple.

Let's scope your project. Send us your workbook and the list of uses: we price the audit, the release plan and the timeline, with a simple application from 2,500,000 FCFA (3,810 EUR). Detailed quote within 48 h. WhatsApp +221 77 596 93 33.