The verdict in three sentences
A self-service billing portal in Dublin costs between €18,000 and €45,000 in 2026, delivered in 8 to 12 weeks. It connects your billing tool (Pennylane, Chargebee, Stripe Billing) to a portal where clients see their invoices and pay online. The most tangible result: automated reminders that cut late payments by 40 % and lighten your finance team's load.
Scope and integrations
This kind of portal is worth its connections: billing, payment and accounting must talk to each other. Here are the blocks and their 2026 cost.
| Block | Description | Indicative cost (€) | Timeline |
|---|---|---|---|
| Client authentication | Secure login, invitations, roles | 3,000 – 6,000 | 1 wk |
| Invoice list & detail | Statuses, PDFs, due dates | 4,000 – 8,000 | 1.5 wk |
| Online payment | Card, SEPA direct debit, receipts | 5,000 – 10,000 | 2 wk |
| Automated reminders | Email/SMS sequences before/after due date | 4,000 – 8,000 | 1.5 wk |
| Billing connection | Pennylane / Chargebee / Stripe API | 5,000 – 12,000 | 2.5 wk |
| Accounting export | Sync to accounting software | 3,000 – 7,000 | 1.5 wk |
A billing + payment core starts at €18,000; with advanced reminders and dual integration, it reaches €45,000.
Cash-flow ROI
The real lever is DSO (average collection period). 2026 estimates for an SME billing €3M/year.
| Metric | Before portal | After portal | Effect |
|---|---|---|---|
| Average DSO | 52 days | 38 days | -14 days |
| Late payments | 25 % | 15 % | -40 % |
| Reminder time / month | 22 h | 6 h | -73 % |
| Reminder cost / invoice | €4.50 | €1.20 | -73 % |
| Working capital tied up | high | reduced | +cash |
On €3M revenue, cutting 14 DSO days frees about €115,000 in cash (3,000,000 × 14/365).
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Mini case study
Sophie, CFO of a software-subscription SME in Dublin (€3M revenue, 400 B2B clients) faces a 52-day DSO and spends 22 hours a month chasing payments. She invests €32,000 in a client portal connected to Pennylane, with card/SEPA payment and automated reminders.
After five months: DSO down to 38 days, i.e. ~€115,000 in cash freed, and reminder time cut nearly fourfold (22 h → 6 h), i.e. 16 hours/month returned to the team. At €40/hour, that's ~€7,700/year of admin cost avoided. The portal pays for itself within the first year, cash included.
FAQ
Which billing tools can you connect? The most common in 2026: Pennylane, Chargebee, Stripe Billing, Sellsy, Zoho. Integration costs €5,000 to €12,000 depending on the API.
Is online payment secure? Yes, via PCI-DSS certified providers (Stripe, Mollie, GoCardless for SEPA). You never store card data.
Do automated reminders hurt client relationships? On the contrary, when well tuned (courteous pre-due reminder, post-due follow-up) they professionalise collection and reduce friction.
How long until go-live? 8 to 12 weeks for a full portal. An invoices + payment MVP can ship in 6 weeks.
Can you handle recurring SEPA direct debit? Yes, ideal for subscriptions: online mandate via GoCardless or Stripe, automatic debits and failure handling.
Let's scope your project. Tell us your billing tool, invoice volume and current DSO, and we'll frame a client portal between €18,000 and €45,000. Detailed quote within 48 h. 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.
