What published VB6 migration prices look like
Most modernization firms quote only after an assessment. One that publishes its benchmarks puts the numbers like this:
| Approach | Published price | A 150,000-line application |
|---|---|---|
| Tool-assisted conversion | $2–$5 per effective line of code | About $300,000–$750,000 |
| Full rewrite | $5–$13 per effective line of code | About $790,000–$1.9 million |
Source: Code District, VB6 migration guide (updated 2 October 2026). The same source puts a tool-assisted conversion of that size at 35–50 weeks with a team of six.
Why line count is the wrong way to price it
Per-line pricing cannot see what actually makes a legacy application hard to move. The same benchmark lists what pushes the cost up, and by how much:
| What the application has | Effect on cost (published benchmark) |
|---|---|
| Many third-party controls | Up to +80% |
| Many reports, or an old report engine | Up to +50% |
| Data access spread through the code | +15–25% |
| No tests or specifications | +20% |
| A regulated domain | +15% |
| Hardware and interop | +12% |
Together these are why two applications of identical size can differ in cost by 2.8× — and why per-line quotes tend to come in low and finish high.
Convert, rewrite, or move it module by module?
A big-bang cut-over is where the rewrite horror stories come from. The alternative is the strangler-fig approach: move one module at a time, prove feature parity for each before it switches, and let the old system keep running the parts that have not moved. Nothing goes dark on a cut-over day, and billing can follow each accepted module.
A traceability matrix answers the real fear in any modernization — that something nobody remembered quietly disappears.
If the source code or documentation is gone
Undocumented systems whose developers have left are the normal case, not the exception. Work can start from a walkthrough of the working system and a schema-only export of the database: the structure of the tables, never the data in them.
What to have ready before you ask for a quote
You do not need a specification. A short note on these is enough to start an honest conversation:
- Roughly how many screens or forms the application has
- Which third-party controls and report tools it depends on
- Which databases and other systems it talks to
- Who uses it, and which parts can never go down
How Pricient quotes a modernization
Modernization starts with an assessment, credited toward the build. It produces a current-state map, an extracted specification, a risk register, a total-cost-of-ownership comparison and a phased quote. We are taking these by enquiry at the moment — tell us what you are running and we will tell you honestly whether it is worth starting.