Keystone

Funding Envelope Calculator

A defensible ±30–40% estimate of the programme team and SI implementation cost at Funding Envelope & Benchmark Costs (S6) — sized before you go to market, so the board has its own benchmark to set aside rather than waiting for the SI's number. Set the programme parameters below; the calculator applies Keystone's role-mix percentages and blended day-rates to produce an envelope range for Board Gate 1 — the board's decision, at the end of that stage, to approve the funding envelope and proceed into market. Software, infrastructure and internal-team costs sit outside this envelope and are shown separately below as wider programme costs.

← Back to Command Centre

Auto-set by size. Override if your programme differs.

Light reduces total effort by 10%. Heavy increases by 15%.

Cost breakdown by role group

Role group Provided by Effort % Effort (days) Rate tier Day rate Cost

SI / Programme team is an indicative split — mixed roles are shown on their predominant side. Tell us to re-assign any to fit your operating model.

Headcount sanity-check

Role group Effort (days) Duration (months) Working days Implied FTE
Headcount is indicative. Some roles (e.g. 1 Business Architect per workstream, 1 SI Functional Lead per workstream) are fixed-per-workstream in practice and don't scale linearly with programme size. The implied FTE is simply the effort divided by the working days in the period — where working days = the phase duration in months × 19.3 — working days a month net of annual leave and public holidays (about 232 a year, not the ~260 gross calendar days), so it reflects days realistically available to the programme. It is the number of full-time people the effort implies over the period. For the role sizing pattern — which roles multiply at which programme size — see the Roles tab on the Testing Command Centre and the programme sizing table on the Roles page.

Wider programme costs

The envelope above covers the programme team and SI implementation only. A board funding decision also has to carry the costs below — shown as rough, list-price indicators for orientation. They are not part of the ±30–40% envelope — Board Gate 1 approves the envelope above, not these. Software is priced at Software Selection (S8) and all wider costs are firmed in the Full Business Case (S12).

Midpoint example for the selected programme size — replace with your own estimate (overtype the figure shown).

Share needing a full/power licence; the rest take a light or self-service licence.

Indicative return — illustrative

What you expect to save or gain per year, from your Benefits Map (S2). Leave blank to just see the break-even figure. Not a vendor projection.

Backfill — optional estimate

Count only materially-seconded roles — roughly half a role or less is usually absorbed internally, so leave it out.

Per day for contractor cover; per hire for recruitment. Default flips when you change the basis.

Also budget separately — not estimated here:
  • Infrastructure / hosting — cloud run cost or on-prem hardware, plus any paid vendor service tier (Microsoft FastTrack, SAP Activate Premium, Oracle Soar) where applicable.
  • Internal client team — their own time — Business Architect, Process Owners, SMEs and Benefit Owners seconded to the programme. The envelope above prices the contracted delivery team at day-rates; your own people's time sits here. (Backfill to cover their day jobs is estimated above.)
  • Third-party integration tooling and middleware.
  • Post-go-live optimisation backlog — funded from Optimisation & Maturity (S19) onward.
Rates published May 2026, reviewed periodically. Derived from IT Jobs Watch UK contract median day-rates for Programme Manager, Solution Architect, Functional Consultant and Developer roles, cross-referenced with Hays Salary Guide and Free-Work, and adjusted for senior D365 programme delivery context based on practitioner experience.

How this estimate is constructed: see the Funding Envelope estimation method page for the full worked example and the logic behind the role-mix percentages.