The verdict in three sentences
In Lagos, a 95-day DSO for an SMB invoicing USD 1 million a year means about USD 260,000 tied up in receivables. A custom reminder automation, at USD 5,000 to 15,000 (roughly 3 to 9 million FCFA), chases the right customer on the right channel at the right time and adds a payment link by card, bank transfer or mobile wallet. Bringing DSO down to 60 days frees close to USD 96,000 of cash, far more than the cost of the project.
What reminder automation costs in 2026
| Module | Essential version | Advanced version | Full version |
|---|---|---|---|
| Invoice import (ERP, Sage, Excel) | USD 1,000 | USD 1,700 | USD 2,500 |
| Personalised email sequences | USD 850 | USD 1,200 | USD 1,500 |
| SMS and WhatsApp Business API | SMS only | SMS + WhatsApp | SMS + WhatsApp + scheduled call |
| Payment link (Paystack, Flutterwave, transfer) | not included | USD 1,500 | USD 2,500 |
| Receivables dashboard | USD 1,150 | USD 2,000 | USD 3,300 |
| Automatic payment reconciliation | not included | USD 1,000 | USD 2,500 |
| Total project (2026 estimate) | USD 5,000 | USD 9,200 | USD 15,000 |
| Monthly costs (SMS, WhatsApp, hosting) | USD 65 | USD 150 | USD 300 |
Delivery takes 6 weeks for the essential version and up to 10 weeks for the full version, including bank and wallet reconciliation.
The reminder sequence that works in Nigeria
Tone matters as much as frequency. Nigerian B2B customers respond much better on WhatsApp than by email, but overly pushy reminders damage the relationship.
| Timing | Channel | Message | Observed payment rate (estimate) |
|---|---|---|---|
| D-5 before due date | polite reminder + PDF invoice | 15 to 20% | |
| D0 due date | reminder + payment link | 20 to 30% | |
| D+7 | SMS + email | firm reminder, balance due | 10 to 15% |
| D+15 | personalised reminder signed by the CFO | 8 to 12% | |
| D+30 | call from account manager | instalment plan offer | 5 to 10% |
| D+45 | formal demand letter | terms and late fees reminder | 3 to 5% |
Combined, these steps get 70 to 85% of invoices paid before 45 days, compared with 40 to 50% with irregular manual follow-up.
Impact on DSO and cash
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| Indicator | Before | After 6 months | Change |
|---|---|---|---|
| DSO | 95 days | 60 days | -35 days |
| Receivables (revenue USD 1M/year) | USD 260,000 | USD 164,000 | USD 96,000 freed |
| Invoices over 60 days late | 28% | 11% | -17 points |
| Finance team time on reminders | 40 h/month | 10 h/month | -30 h |
| Overdraft cost avoided (rate 25%) | baseline | about USD 24,000/year | direct gain |
Mini case study
Chidi, CFO of an IT equipment distributor in Lagos, invoices USD 1 million a year and has a 95-day DSO. He picks the advanced version at USD 9,200, with USD 150 a month in running costs. Six months later, DSO falls to 62 days: about USD 90,000 of cash freed. The company pays down part of an overdraft charged at around 25%, saving roughly USD 22,500 in interest a year, plus 30 hours a month of reminder work an accountant now spends on reconciliation. With Nigerian borrowing rates, the project pays back in about five months on interest alone.
FAQ
How much does overdue invoice reminder automation cost in Lagos? Between USD 5,000 and 15,000 depending on channels, payment link and reconciliation, plus USD 65 to 300 a month in messaging and hosting.
Is it legal to send reminders on WhatsApp? Yes, through the WhatsApp Business API with Meta-approved message templates and customer consent, in line with the Nigeria Data Protection Act 2023. Expect a few US cents per conversation depending on category.
Does it connect to Sage or our ERP? Yes, by API or scheduled export. Sage, Odoo and most ERPs used in Nigeria allow daily invoice import with under 2 weeks of development.
Are payments reconciled automatically? With the advanced version, every payment link carries the invoice reference: 85 to 95% of collections are matched without manual work.
Should we warn customers? It is recommended to announce the new process and restate your payment terms, which reduces negative reactions and disputes.
Let's scope your project. Tell us your revenue, current DSO and invoicing software, and we will price the scope, the budget and the go-live timeline. 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.
