The Real Math of an International Tech Offer: What Your Compensation Doesn't Tell You

The gross number on an international tech offer is the worst possible comparison tool. After taxes, statutory deductions, and the rent on somewhere to live, the gap between two countries' offers usually shrinks by half. A 150% raise on paper turns into a 50% lifestyle improvement once you finish the math.

This applies if you're a Senior Software Engineer in San Francisco evaluating a London offer. Or a Toronto developer considering a New York Series B. Or a Warsaw engineer with a Skilled Worker visa offer in hand. Three different starting points, same problem: the offer letter is the worst place to start.

Below, what to look at instead. One worked example to show how the layers stack. Then a comparison table for the most common moves.

What sits between the gross number and your bank account

Three things, every time.

Financial. Tax structure, statutory deductions, cost of living, currency exposure. The biggest miscalibration most candidates make happens here, in the gap between marginal rate headlines and effective rate reality.

Career. What the role builds for the next move, and how your title and seniority calibrate in a market that doesn't know you yet. The same job title can mean one rung up or one rung down depending on the city.

Operational risk. What happens if the role ends, the visa changes, the company restructures. Costs nothing while everything works. Costs everything when it doesn't.

Most candidates spend 80% of their evaluation time on financial and 20% on career. Operational risk gets the leftover few minutes. That usually inverts the value of the analysis.

Run all three.

The financial reality

Marginal headline rates are noise. Effective rates are signal.

The UK top income tax rate is 45%. The US federal top rate is 37%. California adds up to 13.3%. Ontario combined federal-provincial reaches 53.53%. Polish PIT tops out at 32%.

None of those numbers tell you what you'll pay.

A Senior Software Engineer earning $280,000 total comp in San Francisco loses approximately $103,500 to federal tax, California state tax, Social Security, Medicare, additional Medicare, and the employee portion of health insurance. About 37% of gross.

The same role at £140,000 total comp in London loses approximately £54,000 to income tax (the personal allowance fully tapers above £125,140) and National Insurance. Also about 37% of gross.

The headlines look completely different. The effective rates converge. Run your specific numbers, not the marginal stories.

Cost of living is mostly housing.

A 1-bedroom apartment in central San Francisco crossed $4,000 a month in 2025. Central London runs around £2,300. Toronto downtown is around CAD $2,600. Warsaw central is around PLN 4,500. Everything else, groceries, transit, dining, adds up to 10–20% of the cost-of-living delta. Housing is the rest.

When you compare offers, compare 1BR rents in each city first. That single line item drives most of the cost-of-living adjustment to your take-home gap.

Lost optimization is the layer no one warns you about.

Many senior Polish developers work on B2B contracts with IP-Box, which applies a 5% PIT to qualifying IT activity. Effective deduction rate on B2B with IP-Box runs around 15–20%. On a standard employment contract (UoP), it's closer to 38%.

When that engineer moves to London under a Skilled Worker visa, IR35 rules introduced in 2021 effectively eliminate the option of preserving a B2B structure with a primary employer. They lose the optimization on day one. Same gross compensation, very different take-home.

This pattern repeats across origin markets. German Freiberufler status, Spanish Beckham Law, Israeli oleh chadash benefits. Each is a structure that may or may not survive a cross-border move. Check what optimization you're using today before you assume gross-to-gross comparison tells the truth.

Currency exposure matters when your obligations span borders.

If you have a mortgage at home, child support, family help, or financial commitments that don't move with you, the offer's currency stability is a real risk. A 10% currency shift against a CAD-denominated obligation costs a Toronto-to-NYC mover thousands per year. Build it into the picture, especially for moves where you're keeping ties.

The career reality

Your title doesn't transfer cleanly.

"Senior" in San Francisco usually means 5–8 years of experience and ownership of specific scope. "Senior" in London frequently means the same on paper but with broader expected breadth. "Senior" in Berlin can mean 3+ years and is closer to what San Francisco calls "Mid-level." "Senior" in Warsaw often includes tech lead responsibilities by default.

Your level in the new market may be one rung up or one rung down from where you sit today. Don't anchor on the title in the offer. Anchor on the local market percentile your compensation puts you in. That's the real seniority signal.

Some moves pay off in year three, not year one.

An engineer leaving Warsaw for London at a 2x raise may have made a 0.5x decision in pure year-one financial terms. If the move opens access to UK fintech, FAANG London, or a future US transfer, the present-value comparison breaks. Run financial math for year one. Run career math for year three. Treat them as separate questions with separate answers.

The skills the math doesn't capture.

Operating in a market where no one knows you builds specific skills you can't put on a resume. Getting people to trust you fast, without shared history or a mutual contact to vouch for you. Reading a new ecosystem quickly enough to figure out which relationships matter and how decisions actually get made. Articulating your value in rooms where your track record isn't precedent and doesn't precede you.

These don't show up in compensation comparisons. They compound across moves. An engineer who has rebuilt a professional network from scratch in two cities walks into the third with an ease that earlier-career peers can't fake. That's worth weighing when the financial math comes out close.

The operational risk reality

Visa portability is the risk no one models.

Skilled Worker visa holders in the UK have 60 days to find a new licensed sponsor or leave the country. H-1B holders in the US face similar pressure. In a tech downturn, like late 2022 and early 2023 when more than 280,000 tech workers lost their jobs globally, that window closes fast. Visa-tied workers under those conditions had weeks to relocate families, sell things, and decide.

Evgeny Pavlov, founder of Tech Nomads: "What most candidates don't realise is that visa portability following a tech redundancy typically provides a 60-day window, and in a slower hiring market, that period can close far more quickly than a new offer materialises. In our casework, the most underestimated risk isn't the move itself, but the assumption that a new role will be secured before immigration status expires."

Severance norms aren't transferable, and they're not equal.

A US Senior SWE laid off after three years walks away with whatever the company chooses to offer. There's no statutory minimum. A UK Senior SWE in the same situation has rights to statutory redundancy (1 week per year of service) plus contractual notice (typically 1–3 months at this level). A Canadian Senior SWE under common-law "reasonable notice" doctrine is owed months, often 6–12, particularly at senior levels with longer tenure.

Same person, same role, same circumstances. Fundamentally different financial downside protection depending on where they're employed. Invisible at offer time. Decisive at exit.

Equity vesting can break on cross-border moves.

Some US employers continue vesting unchanged through an international transfer. Others reset the clock. Others treat the move as a "termination event" for unvested equity. Tax events can also trigger at the move: deemed disposal in some jurisdictions, exit tax in others.

If you have meaningful unvested equity, verify the policy in writing before signing. "We transferred Sarah last year and it was fine" is not binding precedent for your case.

Healthcare gaps cost more than people expect.

In the US, leaving a job mid-year before new coverage starts means COBRA premiums of $1,500–2,500 a month for a single person, or an uninsured gap that one ER visit can turn into a five-figure problem. UK and Canada don't have this exposure. Coverage continues regardless of employment status.

Moves into the US system require explicit coverage continuity planning. Moves out of the US system often don't.

One worked example: Warsaw to London

Pick the move that compounds all these layers and watch how they stack.

Setup. Senior SWE in Warsaw, PLN 260,000 total comp on UoP, typical Senior outside FAANG-tier Warsaw roles. Skilled Worker visa offer in London at £130,000 total comp. The kind of offer that looks like an obvious 2.4x raise.

Headline. £130,000 vs PLN 260,000 ÷ GBP/PLN 4.85 = £130K vs £53.6K gross. Headline gap: £76,400 (2.4x raise). The instinctive read: take it. Obviously.

Financial layer. UoP deductions on PLN 260K total around 38% (PIT, ZUS, NFZ health). Net: ~PLN 161,650 (~£33,300). PAYE deductions on £130K also around 38%. Net: ~£80,900. Net gap: £47,600 in favor of London, still a 2.4x take-home increase.

But most senior Polish developers aren't on UoP. If the same engineer was on B2B with IP-Box at home, effective rate was closer to 17–20%, net was ~PLN 215,000 (~£44,300). The move to UK PAYE eliminates that optimization. Net gap becomes £37,600, a 1.9x increase, not 2.4x.

Cost of living layer. London 1BR central ~£2,300 a month (£27,600 a year). Warsaw 1BR central ~PLN 4,500 a month (~£11,100 a year converted). Housing differential: £16,500 a year.

After housing:

• UoP background: lifestyle gap ~£31,000 a year
• B2B background: lifestyle gap ~£21,000 a year

Visa cost layer. Skilled Worker visa, 5-year pathway to Indefinite Leave to Remain: £1,519 visa application + £5,175 Immigration Health Surcharge (£1,035 a year × 5) + £1,000–2,000 solicitor or relocation support if used. Total first-year cost: ~£7,500–9,000 for a single applicant. For a partner and child, roughly 2.5x. A family of three is committing £20,000+ in visa fees alone.

Evgeny Pavlov, founder of Tech Nomads: "What many candidates underestimate is the gap between receiving an offer and actually starting a role when UK sponsorship is required. If an employer needs to issue a Certificate of Sponsorship, verification and compliance checks alone can add four to six weeks on top of a standard notice period. We regularly see candidates hand in their notice before confirming that their prospective employer's sponsor licence is active, creating unnecessary legal and immigration risks."

The real picture. A move that looks like a 150% raise is, in practice:

• UoP background: a 90% lifestyle improvement, minus first-year visa cost
• B2B background: a 50% lifestyle improvement, minus first-year visa cost

The decision is still often "yes," especially for earlier-career engineers building toward UK or EU career architecture, or for those whose families benefit from the move. But it's a different "yes" than the headline implies. It's "moderate financial improvement plus a different career trajectory, traded against £8K of visa investment and a 5-year ILR commitment." Some senior Polish engineers run this math and decide that B2B life in Warsaw, with property ownership and local equity, isn't worth trading. That's a defensible answer when the numbers actually support it.

Five questions your offer letter doesn't ask

Run these before signing any international offer.

1. Sponsor licence status and timeline (if you need a visa). Ask explicitly whether the company holds a current A-rated sponsor licence, when it was last renewed, and whether they've sponsored your specific role type before. Vague answers, third-party routing, or "we'll get one for you" are warning signs.

2. Severance and notice provisions. What statutory minimum applies in this jurisdiction, and what does the company offer above it? Particularly important when moving from at-will (US) to statutory regimes (UK, EU, Canada), or in the reverse direction.

3. Equity vesting on relocation. Does your vesting clock continue, pause, or reset on international transfer? Are tax events triggered at the move (deemed disposal, exit tax)? Get the policy in writing.

4. Healthcare gap. What date does coverage begin, and what's the recommended bridge if you're between schemes? Critical for moves into the US system, where a gap can mean tens of thousands in exposure.

5. Tax residency and bonus timing. When do you legally become tax resident in the new country, and how does the timing of any signing bonus or first-year payment interact with that? A bonus paid before arrival may be taxed only at home. One paid after arrival may be taxed in both jurisdictions until tax treaty relief applies.

Evgeny Pavlov, founder of Tech Nomads: "The most common mistake we see is candidates completing a relocation in Q4 without considering where their bonus will be taxed based on the payment date rather than the period in which it was earned. Timing a move just two months earlier or later can shift a significant portion of that bonus into a higher-tax jurisdiction, and it's rarely identified until it's too late to correct."

How common cross-border moves shake out

The math for five popular moves, condensed to one row each. Figures assume a Senior Software Engineer single filer at market median total comp for the destination market.

Two takeaways.

The "obvious" moves on paper, NYC to Toronto and London to New York, are routinely the most overstated by gross comparison. The lifestyle gap is roughly a quarter of what the offer letters suggest.

The Polish B2B optimization story is the single largest hidden variable in cross-border moves into UK or US PAYE. Half the apparent raise can evaporate before housing even enters the picture. Anyone considering a move from a B2B-heavy European tech market to UK PAYE or US W-2 needs to run that math first.

The bottom line

The biggest financial mistake in international job decisions is comparing offers in their currency of origin and stopping there. The second biggest is treating tax structures and cost of living as footnotes. The third is ignoring operational risk, which costs nothing while everything goes well and costs everything when it doesn't.

The actual decision is rarely about whether one offer is "better." It's about what each one builds, given your specific starting point, your career stage, and your tolerance for the trade-offs that don't appear on either document.

The math gives you the starting point. The framework gives you the structure. The five questions give you the negotiation prep.

About Tech Nomads

This piece draws on practitioner expertise from Tech Nomads, a UK-based global mobility platform working with tech professionals on UK, US, and UAE visa pathways. Founded in 2018 by Evgeny Pavlov, Tech Nomads works with engineers, founders, and HR teams on relocation, with particular depth on UK Skilled Worker, Global Talent, and Innovator Founder routes. For practical guidance on the visa and relocation logistics referenced above, see Tech Nomads.

Frequently Asked Questions

How much does an international tech salary actually shrink after taxes and cost of living?

Depends on the move. For Senior SWE moves between major tech markets, the headline gross gap typically shrinks by 25–50% after tax and statutory deductions, then by another 10–30% after cost of living. A $90K gross gap commonly ends up as a $40–50K lifestyle gap. For the Warsaw to London move, a 2.4x raise on paper turns into a 1.9x raise after lost B2B optimization, before housing adjustment.

What is the most expensive cross-border tech move on cost of living?

For tech moves, relocating into San Francisco or Manhattan from any market outside California or the New York metro is the largest housing-cost step up. A 1BR in central San Francisco crossed $4,000 a month in 2025; Manhattan ranges $4,500–5,500. London, Toronto, and Warsaw rents are roughly 30–60% lower. Housing is the single biggest line item driving cost-of-living differentials between major tech markets.

What is the most underestimated risk in an international tech move?

Visa portability. Skilled Worker visa holders in the UK have 60 days to find a new licensed sponsor or leave the country if the sponsoring role ends. H-1B holders in the US face similar pressure. In a tech downturn, that window can close fast. Severance norms also vary widely between jurisdictions: the UK has statutory redundancy pay tied to length of service, the US has no statutory minimum, Canada applies "reasonable notice" doctrine that can mean 6–12 months for senior employees.

How do I compare a tech offer across countries if I don't have a local market reference?

Run three layers. First, compare gross to net by deducting income tax, statutory contributions, and mandatory health and pension contributions. Second, adjust for cost of living, starting with 1BR central rent comparison. Third, factor in operational risk: visa portability, severance, equity vesting on cross-border transfer, healthcare continuity. Use a salary intelligence tool like PayScope to anchor your offer against the local market percentile, which is more useful than the median when negotiating.

Why does my Polish or EU self-employment tax optimization stop working in the UK?

UK IR35 rules introduced in 2021 effectively closed the option of preserving a B2B contractor structure with a single primary employer. Most engagements with a primary employer now require PAYE employment, which eliminates the tax-rate advantages senior developers often have on B2B with IP-Box in Poland, or on Freiberufler status in Germany. The move from a structure with a 15–20% effective rate to UK PAYE at 36%+ can quietly erase half the apparent raise from a cross-border offer.

Before you sign: see where your specific offer sits on the local market distribution. PayScope analyzes your offer against live compensation data by city and seniority. The difference between a "good" offer and a "you can negotiate this up another 10%" offer is usually right there in the percentile chart.

For visa, sponsor licence, and relocation logistics on the operational risk side, Tech Nomads is the practitioner reference for UK, US, and UAE pathways.