The verdict in three sentences
For a 6,000 m² warehouse in Dublin, a vertical SaaS WMS (800-2,500 EUR/month) is enough as long as your processes stay standard, while a custom WMS (60,000-120,000 EUR) is justified by atypical flows or deep ERP integration. The real financial stake is pick quality: moving from 3.2% to 0.8% errors is often worth more than the price gap between the two options. Decide on 3-year TCO and throughput, not the monthly license.
Vertical vs custom: the real match
A WMS drives locations, picking, replenishment, cycle counts and traceability. The choice hinges on how specific your flows are.
| Criterion | Vertical WMS (SaaS) | Custom WMS |
|---|---|---|
| Upfront cost | 5,000-20,000 EUR (setup) | 60,000-120,000 EUR |
| Recurring cost | 800-2,500 EUR/month | Hosting 200-500 EUR/month |
| Barcode/RFID terminals | 250-600 EUR/unit | 250-600 EUR/unit |
| Deployment time | 1-3 months | 5-9 months |
| Fit for atypical flows | Limited | Full |
| ERP integration | Standard connectors | Bespoke |
| 3-year TCO (indicative) | 40,000-110,000 EUR | 75,000-140,000 EUR |
Below ~4,000 SKUs and without strong traceability constraints, vertical almost always wins. Beyond that, or with cross-docking and complex put-away rules, custom regains the edge over 3 years.
The quantified decision grid
Four variables settle the debate. Weight them to your reality.
| Variable | Leans vertical | Leans custom |
|---|---|---|
| Number of SKUs | < 4,000 | > 8,000 |
| Throughput (lines/day) | < 2,000 | > 5,000 |
| ERP integration | Standard | Deep / real-time |
| Budget model | OPEX preferred | CAPEX amortizable |
| Specific flows | Few | Cross-docking, kitting, dating |
On performance, a well-deployed WMS moves picking errors from 3.2% to 0.8% and lifts picking productivity by +18%. In a 6,000 m² warehouse, that is the line item that repays the project.
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
Mini case study
Sophie, logistics director of a Dublin distributor (6,000 m², 45 pickers, 4,500 lines/day), runs 3.2% picking errors. Each error costs ≈ 22 EUR (return, credit, re-pick), i.e. ≈ 316,800 EUR/year. Deploying a vertical WMS at 1,800 EUR/month (21,600 EUR/year) plus 60 terminals at 400 EUR (24,000 EUR), she cuts errors to 0.8%. Saving: ≈ 237,600 EUR/year. The +18% picking productivity gain also frees capacity to absorb growth without hiring. ROI reached in under 3 months.
FAQ
How much does a WMS cost for a 6,000 m² warehouse in 2026? A vertical SaaS WMS runs 800-2,500 EUR/month by volume, plus 5,000-20,000 EUR setup. A custom build lands between 60,000 and 120,000 EUR, hosting extra.
Barcode or RFID? Barcode remains the most cost-effective standard (250-400 EUR/terminal). RFID (400-600 EUR/unit plus tags) is justified on very high-throughput flows or automated mass inventory.
How many errors does a WMS really eliminate? A careful deployment moves picking errors from ~3% to under 1%. This is a 2026 order of magnitude; the gain depends mostly on guided-pick rigor and training.
Vertical or custom: how to decide fast? Under 4,000 SKUs and standard flows, take vertical. Above 8,000 SKUs, with cross-docking or real-time ERP integration, custom pays off over 3 years.
What deployment time should I plan? 1 to 3 months for a configured vertical, 5 to 9 months for a custom WMS including stock migration, location mapping and team training.
Let's scope your project. Give us your surface area, SKU count, throughput and ERP: we'll quantify the vertical vs custom scenario and its 3-year TCO. 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.
