The verdict in three sentences
For a trade association with 600 member companies, a shared spreadsheet costs more than it looks: manual chasing, forgotten renewals, a directory that is never up to date. A custom member portal costs between 25,000 and 60,000 GBP in London in 2026 for a 10 to 14 week project, while an association SaaS runs 400 to 1,200 GBP per month with real limits on voting, gated documents and accounting exports. Custom becomes worthwhile as soon as the association has its own subscription rules (banded by headcount, turnover or section) and needs clean exports to its accounting software.
What a chief executive actually manages in 2026
In London, as in most UK trade bodies (construction, tech, food, logistics), the chief executive or membership director wears three hats: subscription collector, network organiser and publisher of members-only content. With 600 members, volume is already significant: 600 renewal invoices, 2 to 3 reminders each, 40 to 60 events a year, an AGM with a vote and members-only legal briefings.
The modules expected from a professional member portal:
- Online subscription payment (card, Direct Debit via Bacs, bank transfer with reconciliation), automatic VAT invoice and receipt.
- Configurable fee bands: by headcount, by declared turnover, by section or trade.
- Member directory with filters (trade, borough, accreditation), with company profiles updated by members themselves.
- Gated documents: briefings, contract templates, market notes, with permissions per section.
- Online votes and consultations for the AGM and committees, with quorum and exportable minutes.
- Accounting export (journal entries for Xero, Sage or QuickBooks).
Custom build or association SaaS: the comparison
| Criterion | Association SaaS | Custom member portal |
|---|---|---|
| Upfront cost | 0 to 3,000 GBP setup | 25,000 to 60,000 GBP |
| Recurring cost | 400 to 1,200 GBP per month | 200 to 600 GBP per month (hosting, maintenance) |
| Complex fee bands | Often limited to 3 to 5 fixed rates | Unlimited rules (headcount, turnover, section) |
| AGM votes with quorum | Paid add-on or missing | Included, matched to articles of association |
| Accounting export | Generic CSV | Journal entries in your software's format |
| Data ownership | With the vendor | With the association |
| Time to go live | 2 to 4 weeks | 10 to 14 weeks |
Over 5 years, a SaaS at 800 GBP per month adds up to roughly 48,000 GBP, in the range of a custom build, without control over your business rules. The decision therefore hinges on how complex your fee structure is and how valuable your members-only services are.
Detailed member portal budget for 2026
| Work package | Estimated effort | Indicative budget |
|---|---|---|
| Discovery, board workshops, wireframes | 8 to 12 days | 5,000 to 8,500 GBP |
| Member accounts, roles, sections | 6 to 10 days | 4,000 to 7,500 GBP |
| Subscriptions, online payment, automated reminders | 8 to 14 days | 5,500 to 11,000 GBP |
| Directory and company profiles | 4 to 8 days | 3,000 to 6,500 GBP |
| Gated documents and AGM voting | 6 to 12 days | 4,000 to 10,000 GBP |
| Accounting export and spreadsheet migration | 3 to 6 days | 2,000 to 5,000 GBP |
| Testing, training, launch | 3 to 7 days | 1,500 to 11,500 GBP |
| Total | 38 to 69 days | 25,000 to 60,000 GBP |
These are 2026 order-of-magnitude figures seen in the London market for a mid-sized agency or senior freelance team, excluding VAT. Payment fees come on top: about 1.5 % per UK card transaction and around 0.20 to 0.40 GBP per Direct Debit collection.
Watch points: UK GDPR requires a record of processing and a retention period for former members' data (3 years after leaving is common practice). Electronic voting must follow your articles of association: check with your adviser that remote AGMs are allowed, or amend the articles before launch.
Mini case study
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James, chief executive of a construction trade association in London, manages 600 members with an average subscription of 1,100 GBP. Each year about 14 % of subscriptions are paid late or not at all, around 92,400 GBP of potential lost income. He also spends about 6 hours a week chasing payments and updating the directory.
With a member portal at 45,000 GBP and automated reminders at day 15, 30 and 45, the goal is to bring arrears down to 6 %, recovering 48 members and 52,800 GBP in extra subscriptions per year. Add 250 hours of admin time freed up. In this scenario the project pays back in a little over 10 months, to be validated with your real figures during discovery.
FAQ
How much does a member portal for 600 members cost?
Budget 25,000 to 60,000 GBP in London in 2026 depending on the fee structure, voting and accounting export. Hosting and maintenance add 200 to 600 GBP per month.
How long does it take to go live?
Usually 10 to 14 weeks, including 2 weeks of discovery and 2 weeks of testing. A launch timed for a January renewal cycle means starting in September.
Can we migrate our current spreadsheet?
Yes, migrating 600 records and 3 years of subscription history takes 3 to 6 days. Cleaning duplicates beforehand is what takes the longest.
Is an online AGM vote legally valid?
It is if your articles of association allow it and the tool guarantees identification, ballot secrecy and quorum. Time-stamped minutes exported to PDF secure the evidence.
Do we need a London-based supplier?
No, around 80 % of the project runs remotely with 4 to 6 video workshops. A kick-off meeting with the board remains useful to validate the fee bands.
Let's scope your project. Send us your fee structure, member count and priority modules: we will price a member portal in work packages, with an indicative budget and a 10 to 14 week plan. Detailed quote within 48 h via our form. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
