Tax Data Changelog

Naming a source proves where a number came from. It does not prove anyone is still looking at it — and tax figures stop being right quietly, in the middle of a year, without anyone announcing it to the people who built on them. This is the record of every change to the data behind 15 countries: rules that moved, figures we corrected against the statute, and coverage we added.

Roughly half of what follows is our own figures being wrong and being found. That is deliberate. A tax-data vendor with no corrections to show is one that has not checked.

3 rule changes followed10 corrections published7 coverage additionslast change 2026-08-28
  1. New coverageAll countries

    Employer cost, and comparison on a target net

    POST /compare now returns employer social security and total employer cost per country, and accepts basis: NET — hold the take-home constant and every country is grossed up to reach it, ranked by what the hire costs. Delivering €48,000 net costs €62,359 in Bulgaria and €105,956 in Italy.

    Source: Existing per-country employer rates, exposed through /compare

  2. We correctedAll countries

    Five published rates did not match the engine

    Page copy had drifted from the calculators while every calculation stayed correct: Greek EFKA was written as 13.87% (engine: 13.37%), the Spanish scale as topping out at 49% (47%), the Dutch first bracket as 36.97% (35.75%), the Portuguese first band as 13% (12.5%) and Spanish employee social security as 6.4% (6.50%). Rates quoted in prose are now interpolated from one declared source and a test fails if any page contradicts it.

    Source: Each country's own calculator constants

  3. New coverageAll countries

    Marital status reached the website

    The API had accepted maritalStatus from the start and five calculators branch on it — France, Ireland, Malta, Switzerland and Poland — but the web form never asked, so every visitor received the single figure.

    Measured effect: At €60,000 the married figure is €4,511 a year higher in France and €3,800 higher in Ireland

    Source: Per-country married bands, tariffs and credits

  4. Rule changedCzechia

    A mid-year law moved the self-employed figures retroactively

    Zákon č. 90/2026 Sb. took effect on 1 July 2026 but applies from 1 January, cutting the first paušální daň band from CZK 9,984 to CZK 9,162 a month and the OSVČ minimum assessment base from 40% to 35% of the average wage. Anyone who paid the enacted January amount for the first half of the year is owed CZK 4,932 back.

    Source: zákon č. 90/2026 Sb.

  5. New coverageCzechia

    Czechia added as the fifteenth country

    Employee and self-employed, including all three self-employed regimes and the refundable child bonus. The superhrubá mzda was abolished in 2021 and any calculator still applying it overstates Czech tax by about a third.

    Source: Zákon o daních z příjmů; ČSSZ and VZP 2026 rates

  6. We correctedGreece

    EFKA healthcare had been a full point too high on both sides

    The healthcare branch was cut by one percentage point with effect from 1 January 2025 — in kind 1.65% and in cash 0.40% for the employee, 3.80% and 0.25% for the employer. Our rates were still the pre-cut ones: employee healthcare 2.15% → 2.05% and employer 4.30% → 4.05%, taking the totals from 13.87% to 13.37% and from 22.29% to 21.79%. Many published tables still quote the old pair.

    Measured effect: Net pay on a €30,000 salary rose €108 a year

    Source: PwC Greece tax summary; e-EFKA circular

  7. We correctedBulgaria

    The employer total was understated and the employee split was wrong

    Employer contributions were modelled at 18.02% with two funds missing entirely — ОЗМ at 2.10% and ТЗПБ at 0.40% — while the pension line was 1.6 points too high; the correct third-category total is 18.92%. On the employee side the 13.78% total was already right but ОЗМ had been folded into pension, so the breakdown told the user the wrong thing about where the money went.

    Source: НОИ / ЗБДОО 2026, third labour category

  8. We correctedSpain

    The MEI pension levy was missing entirely

    The mecanismo de equidad intergeneracional has applied since 2023 and was not modelled at all: 0.90% in total for 2026, split 0.15% employee and 0.75% employer, on top of the familiar rates. Employee social security moved from 6.35% to 6.50% and the employer side to 30.65%. It rises again every year to 1.2% by 2029.

    Source: Orden PJC/297/2026; MEI schedule

  9. We correctedNetherlands

    The Zvw health contribution and its ceiling had gone stale

    Both move every year and ours were pre-2026: the employer contribution 6.68% → 6.10%, the maximum contribution income €71,628 → €79,409, and the self-employed rate 5.43% → 4.85%. The nominal basisverzekering premium we disclosed was also a pre-2025 figure.

    Source: Staatscourant, published 13 November 2025

  10. We correctedIreland

    PRSI was still blending the previous year's rates

    Irish PRSI changes mid-year, so a full calendar year is a blend. The employer lower band was 8.9625% — the 2025 pair — instead of 9.0375%, and the threshold between the employer bands had risen to €552 a week on 1 January (from €527). The Single Person Child Carer Credit went from €1,750 to €1,900 and the Class S annual minimum from €500 to €650.

    Source: Budget 2026; Class A and Class S PRSI schedules

  11. We correctedGermany

    A stale solidarity-surcharge threshold charged Soli to people who owe none

    The Freigrenze is indexed every year — €18,130 in 2024, €19,950 in 2025, €20,350 in 2026 — and leaving it behind means charging the surcharge to employees who have passed out of it. The average GKV supplementary contribution was also updated to 2.9% for 2026.

    Source: SolZG; BMG average Zusatzbeitrag 2026

  12. We correctedSwitzerland

    An unemployment surcharge that had lapsed by law was still being charged

    The 1% ALV Solidaritätsbeitrag — 0.5% on the employee — ended by operation of law once the unemployment-insurance debt was repaid, and was still in our rates. The Zürich cantonal Grundtarif band widths were replaced with the published ones for Steuerperiode 2026.

    Source: BSV Beträge ab 1.1.2026; Zürich § 35 StG, Steuerperiode 2026

  13. We correctedFrance

    Missing high-income surcharge and a stale abattement floor

    The contribution exceptionnelle sur les hauts revenus was not modelled at all — 3% and 4% above €250,000 and €500,000 for a single person, doubled for a couple — and the 10% abattement floor was €504 rather than €509. The CET contribution was also absent.

    Source: Loi n° 2026-103 du 19/02/2026; arrêté du 22/12/2025 (PASS)

  14. New coverageCyprus

    Cyprus added as the fourteenth country

    Social insurance and GESY, with the two ceilings that differ: insurable earnings are capped at €68,904 while GESY runs to €180,000 across all income sources, and the employer's Social Cohesion Fund is not capped at all.

    Source: Social Insurance Services; GESY contribution schedule 2026

  15. We correctedPortugal

    A deduction frozen for years is now indexed, and ours was the frozen one

    The dedução específica sat at €4,104 for a long time until the 2024 reform tied it to 8.54 times the IAS. With the 2026 IAS at €537.13 that is €4,587.09. Carrying the old constant silently overstated Portuguese tax, and it now moves every January.

    Source: CIRS art. 25; IAS 2026 = €537.13

  16. Rule changedBulgaria

    The contribution ceiling rose mid-year, and is now set in euro

    Maximum monthly insurable income went from €2,111.64 to €2,300 on 1 August 2026 and is legislated to hold through 2028. Since the euro changeover the figure is set in euro directly rather than converted from a lev amount. A full 2026 payroll year straddles both ceilings.

    Source: ЗБДОО 2026 — Закон за бюджета на държавното обществено осигуряване

  17. New coverageMalta

    Malta added as the thirteenth country

    Class 1 contributions are billed weekly against a weekly ceiling, so they are computed in weeks and multiplied by 52 — annualising first overstates anyone near the cap. Secondary sources quoted €45.19 and €47.41 for the weekly maximum; both were stale 2024 and 2025 figures.

    Source: Department of Social Security contribution rates 2026

  18. Rule changedGermany

    The whole German tariff rolled over to the 2026 formula

    Germany does not have brackets to bump; § 32a defines a polynomial, and every constant in it moves. The basic allowance went from €12,084 to €12,348, the zone boundaries from €17,005 and €66,760 to €17,799 and €69,878, and the coefficients inside the formula changed with them. Alongside it the pension ceiling became a single unified figure of €8,450 a month — the separate East and West caps ended — the health ceiling rose to €5,812.50 and the average supplementary health contribution from 0.85% to 1.45% on the employee side.

    Source: § 32a EStG for 2026; Sozialversicherungs-Rechengrößenverordnung 2026

  19. New coverageAll countries

    Portugal and Spain added, with their special regimes

    Both modelled for employees and the self-employed from the start, including the regimes people actually move for: Portugal's IFICI flat 20% for new residents in qualifying activities, and Spain's Beckham Law at a flat 24% up to €600,000.

    Source: CIRS and IFICI; Ley del Impuesto sobre la Renta, régimen de impatriados

  20. New coverageAll countries

    The first four countries: Greece, Bulgaria, Germany and the Netherlands

    The starting point of the engine, and of this record. Each country was written as its own calculator against its own statute rather than as a shared bracket table with different numbers in it — which is why Germany could later take a formula rollover and Bulgaria a euro changeover without either affecting the other.

    Source: Per-country statutes and social-security schedules

Entries run from 2026-04-06 to 2026-08-28. Presentation and interface work is not listed unless it changed a figure someone was shown.

About this record

Why publish your own mistakes?
Because a tax-data vendor who has never been wrong is one who has not checked. Rates move mid-year, authorities correct their own circulars, and figures that were right last January quietly stop being right. What matters to anyone relying on this is not that we were perfect but that someone is looking, that findings are traced to the statute, and that changes are dated. A log with only good news would be worth less, not more.
How often is the data checked?
Every country's figures are read from the authority or the statute rather than a summary, and each calculator carries its own source list. Checks happen when a country is added, when a rule is reported to have moved, and in a full pass before each tax year. Mid-year changes are applied when they take effect — Czechia's 2026 self-employed law is here because it landed in July and applied retroactively to January.
What counts as a change worth listing?
Anything that moves a number a user or an API client would see: a rate, a threshold, a ceiling, a credit, a regime, or a country. Interface and presentation work is not listed here unless it changed a figure someone was shown.
How do I get notified?
There is no feed yet. If you build on the API and need advance notice of changes for a specific country, say so when you get in touch — knowing which countries customers actually depend on is what decides where the next verification pass goes.

Building on this data?

Every figure behind these entries is available through the API, and each country's sources are published in full. If you need advance notice of changes for particular countries, that is a conversation worth having — customer dependence is what decides where verification effort goes next.