The verdict in three sentences
A credible timeline can't be compressed: custom means scoping, design, development then testing, each phase gating the next. 2026 timelines range from 6-9 weeks for a brochure site to 4-8 months for a business app. The top cause of delay is not technical but client availability: late sign-offs and missing content.
Timeline by project type in 2026
These ranges assume an available team and a responsive client. Add 20 to 30 % if sign-offs drag or scope shifts mid-project.
| Project type | Total duration | Scoping | Design | Dev | Testing |
|---|---|---|---|---|---|
| Brochure site | 6-9 wks | 1-1.5 wks | 1.5-2 wks | 2.5-4 wks | 1-1.5 wks |
| Site + blog + SEO | 8-12 wks | 1.5 wks | 2 wks | 3.5-6 wks | 1.5-2.5 wks |
| E-commerce | 10-16 wks | 2 wks | 2.5-3 wks | 4.5-8 wks | 2-3 wks |
| B2B extranet | 12-20 wks | 2.5 wks | 3 wks | 5-11 wks | 2.5-3.5 wks |
| Business app | 4-8 months | 3-5 wks | 3-5 wks | 10-22 wks | 4-7 wks |
Causes of delay and payment milestones
A timeline is secured as much by contract as by method. Tying payments to milestones aligns interests and makes each slippage visible.
| Cause of delay | Frequency | Timeline impact | Countermeasure |
|---|---|---|---|
| Late client sign-offs | Very common | +2-4 wks | Contractual sign-off SLA |
| Missing content/copy | Common | +1-3 wks | Content due at kick-off |
| Scope creep | Common | +3-8 wks | Formal change orders |
| Third-party integrations | Medium | +1-4 wks | Upfront POC |
| Incomplete testing | Medium | +1-2 wks | Test plan from design |
Typical payment milestones: 30 % on order, 30 % on design sign-off, 30 % on delivery to testing, 10 % on go-live. Each month of slippage for a team costing 70,000 EUR/year runs about 5,800 EUR in mobilization, before the lost revenue from a delayed launch.
Mini case study
Aoife, project manager at a Dublin manufacturer, wants a B2B e-commerce store live for a trade show in 14 weeks. The vendor estimates 12 to 16 weeks. Aoife secures the timeline by booking two sign-off workshops a week, supplying all visuals at kick-off and freezing scope after design. Result: delivery in 13 weeks, just before the show. Had she let sign-offs slide, the +3 weeks would have made her miss the event, at an estimated 40,000 EUR loss in show orders.
FAQ
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
Can a brochure site ship in 3 weeks?
Yes for a configured template with supplied content, no for true custom. An original design plus specific development needs at least 6 weeks to hold quality.
Why does testing take so long?
Testing is 20 % of the project because it covers functional tests, browser compatibility, performance and fixes. Rushing it creates costly technical debt after launch.
What happens if scope changes mid-project?
Every unplanned change goes through a change order priced in time and cost. Without that frame, the project drifts by weeks without anyone truly deciding it.
Do timelines include content production?
Rarely by default. Copywriting and visuals are often client-side; their delay is the top slippage cause. Price them explicitly if you delegate them.
How do I make a timeline reliable?
Break into sprints with visible deliverables, contractualize sign-off SLAs and tie payments to milestones. Weekly transparency avoids nasty surprises.
Let's scope your project. Give us the project type, target date and your availability for sign-offs, and we will build a realistic timeline with milestones. 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.
