Forecast matrix
Planned hours per person and month — with live plan/actual coverage.
Time & material billing
From forecast to finished e-invoice — in one system.
lumen.tm covers the entire billing cycle: contracts with clear rules, day-level time tracking, client sign-off by signature and invoices as ZUGFeRD e-invoices — archived immutably.
Facts, not buzzwords
Built for clean billing
- EN 16931
- Standard of the embedded e-invoice (ZUGFeRD/Factur-X)
- 2
- Capture modes per contract: day-level or monthly total
- 4
- Contract states with defined transitions — draft to completed
- 0 €
- Amounts visible to team members — rates and margins stay confidential
Contract management
The contract sets the rules — once
Every client engagement gets a contract as its central master record: unique contract number, exactly one client, term, optional hour budget and billing rhythm. Time tracking, month-end closing and invoice dispatch all build on it — no side agreements in Excel.
- Two capture modes: day-level (with activity report) or monthly total
- Booking deadline locks the previous month automatically — default: the 25th
- Optional client sign-off: invoice only after the signed activity report
- Early-payment discount as a note — the invoice amount stays unchanged
Approvals & month-end closing
Only approved work gets invoiced
Team members approve their month; optionally the client signs the activity report. Only then is the invoice created — with a preview before closing. A closing can be reversed traceably; the cancelled invoice is kept as a record.
- Monthly approval per team member and contract
- Client sign-off by signature — invoice only after all signers have approved
- Invoice preview before closing
- Reopening is documented — no silent rewriting
Features
The complete billing cycle, one system
From planned forecast to dispatch log — every step connects, without tool switching or Excel bridges.
Time tracking
Daily entries with named rate categories such as “on-site” or “remote”.
Dashboard
Active contracts, forecast revenue, coverage and budget warnings.
Reminders
Automatic nudges for missing hours — before the booking deadline.
Reports & dispatch
Monthly reports as PDF/XLSX, scheduled email dispatch with delivery log.
Document templates
Logo, colours, bank details, number range, tax rate and payment terms.
E-invoicing & archive
Invoices that stand up to an audit
Every outgoing invoice is created as a hybrid e-invoice: a readable PDF/A-3b with embedded XML per EN 16931 (ZUGFeRD/Factur-X) — matching the German B2B e-invoicing mandate. Finalised documents are archived immutably, and every relevant change is captured in the audit log.
- Hybrid e-invoice: PDF/A-3b with factur-x.xml (EN 16931 COMFORT profile)
- Fail-open: a clean PDF rather than an invalid e-invoice
- Document archive — final invoices and reports are immutable
- Audit log: who changed which field and when, with diff view
Common questions
What billing owners ask us
What is time & material billing?
The client pays for actual effort — hours or days at agreed rates — instead of a fixed price, typically with a monthly invoice. lumen.tm covers exactly this cycle: contract, capture, approval, invoice, dispatch.Do team members see hourly rates or amounts?
No. Managers see all amounts, team members only hours. This is enforced twice: the UI hides amounts, and the server additionally strips monetary fields from every response — fail-closed, even for direct API access.Does the invoice meet the e-invoicing mandate?
Every outgoing invoice is created as a hybrid ZUGFeRD/Factur-X e-invoice per EN 16931 (COMFORT profile) — a PDF/A-3b with embedded XML. It covers the standard tax category with a rate above 0 %; special cases such as reverse charge deliberately fall back to the readable PDF.How does client sign-off work?
With day-level capture, a contract can require the client to sign the activity report before the invoice is dispatched. The invoice only goes out once all signers have approved — the status is visible at any time.Where is the data stored?
On EU infrastructure with data residency in Frankfurt — permanently enabled in the product, not optional. The interface is German-language, default currency Euro, timezone Europe/Berlin.What does lumen.tm cost?
Three plans — Starter, Pro and Enterprise — billed per seat via Stripe, monthly or yearly. We publish final prices once they are approved; until then, conditions are aligned in the demo call.
Demo
Your billing cycle, played through end to end
In 30 minutes we show — using your contract structure — how lumen.tm connects forecasting, time tracking, approvals and e-invoicing. Direct, no detours.