The verdict in three sentences
In a New York HR consulting firm with 40 consultants, 5 % of billable time lost to unreliable time entry represents about 630,000 USD of revenue per year. An off-the-shelf PSA (Professional Services Automation) costs 35 to 80 USD per user per month, while a custom build sits between 60,000 and 150,000 USD as a 2026 market estimate. The right choice depends less on the licence price than on the gap between your processes and the tool's standard model.
What engagement management software must track
An HR consulting firm sells expert time: executive search, HR compliance audits, restructuring support, leadership training. Its vital metrics fit in a handful of numbers that most firms still compute by hand in a spreadsheet on the 5th of the month.
| Metric | Definition | Common target (2026 market estimate) | Data source |
|---|---|---|---|
| Utilization rate | Billed hours ÷ available hours | 70 to 80 % for a consultant, 40 to 55 % for a partner | Timesheets |
| Time entry within 48 h | Time logged within two days | Above 95 % | Timesheets |
| Project margin | Fees minus fully loaded cost of hours used | 35 to 50 % | Time, payroll costs |
| Fixed-fee overrun | Hours used beyond the sold budget | Under 10 % | Project budget |
| Billing lag | Days between milestone and invoice | Under 5 days | Billing |
| DSO | Average payment delay | 45 to 60 days | Accounting |
The breaking point is time entry. When a consultant fills in the timesheet from memory on Friday evening, the 2 or 3 hours lost each week are never billed and project margin becomes fiction.
Off-the-shelf PSA or custom build: the numbers
| Criterion | Off-the-shelf PSA | Custom build |
|---|---|---|
| Entry cost | 5,000 to 25,000 USD of configuration | 60,000 to 150,000 USD of development |
| Annual cost for 40 users | 16,800 to 38,400 USD (35 to 80 USD per month) | 10,000 to 25,000 USD of maintenance and hosting |
| Time to go live | 4 to 10 weeks | 4 to 7 months |
| Mixed engagements (fixed, T&M, contingency) | Often partial on contingency fees | Modelled on your contracts |
| HRIS and payroll integration | Standard connectors | Any tool, including in-house ones |
| Client AP portals and accounting | Depends on vendor connectors | Direct link to QuickBooks, NetSuite or client portals |
| 5-year cumulative cost | 90,000 to 215,000 USD | 110,000 to 275,000 USD |
All these amounts are 2026 market estimates. Over 5 years, both options end up in a similar cost zone. A custom build pays off when the firm bills contingency fees on placements, mixed fixed-fee engagements and expense re-billing that PSAs handle poorly, or when it wants a client portal under its own brand.
Another point to plan for: invoicing workflows. The US has no federal e-invoicing mandate, but large clients increasingly require invoices to be submitted through their procurement portals with PO numbers and line-level detail. Engagement software that produces structured invoices and pushes them to accounting and client portals removes double entry.
The steps of a successful project
| Step | Indicative duration | Watch-out |
|---|---|---|
| Process and standard contract audit | 2 to 3 weeks | List every real billing mode |
| PSA or custom decision | 1 week | Test 2 PSAs on 3 real engagements |
| Configuration or development | 6 weeks to 5 months | Prioritise mobile time entry |
| Migration of live engagements | 2 weeks | Budgets, hours used, invoices issued |
| Pilot with one team | 4 weeks | Measure 48 h time entry rate |
| Rollout and steering rituals | 2 weeks | Monthly project margin review |
Mini case study
Illustrative example: Rachel, managing partner of an HR consulting firm in New York, leads 40 consultants billed at an average of 225 USD per hour over 1,400 billable hours a year. Potential revenue: 40 × 1,400 × 225 = 12,600,000 USD. The 5 % of unlogged time weighs 630,000 USD.
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- Goal: recover 3 points of billable time, i.e. 378,000 USD per year.
- PSA option: 40 × 55 USD × 12 = 26,400 USD per year, plus 15,000 USD of configuration.
- Custom option: 100,000 USD, plus 18,000 USD of annual maintenance.
- In both cases, payback comes within 2 to 4 months.
The decision therefore hinges on functional fit, not on price.
FAQ
How much does a PSA cost for a consulting firm in New York in 2026?
As a market estimate, allow 35 to 80 USD per user per month, i.e. 16,800 to 38,400 USD per year for 40 consultants. Initial configuration adds 5,000 to 25,000 USD depending on the number of billing modes.
When does a custom build become worthwhile?
When more than 30 % of your engagements fall outside the PSA's standard model: contingency fees, fixed fees with variable milestones, complex expense re-billing. Over 5 years, the total cost of a custom build, 110,000 to 275,000 USD, comes close to that of a PSA.
How can we improve time entry compliance?
Mobile entry in under 30 seconds, automatic reminders the next day and blocking expense claims until the week is logged are often enough to exceed 95 % of time entered within 48 h.
Should the software handle client invoicing portals?
At minimum it should produce structured invoices with PO references and export them to your accounting system. For clients using procurement portals, a direct connector saves 10 to 20 minutes per invoice.
What timeline should we plan for a custom build?
From 4 to 7 months between the process audit and full rollout, including a 4-week pilot with one team to validate utilization and project margin.
Let's scope your project. Describe your billing modes, headcount and current tools on our quote form: we scope the perimeter and timeline, PSA or custom. 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.
