Spain: fourteen payslips in a twelve-month year
Spain is the interesting case. Salaries there are normally paid in fourteen instalments: twelve monthly payments plus two extra ones, usually in July and December. A 42,000 euro Spanish salary shows 3,000 on the payslip, not 3,500, so the tool shows the instalment as well as the twelfth. Some collective agreements spread the extra pay across twelve months instead, which is worth checking on your own contract.
This matters beyond curiosity. Quote the monthly twelfth to a Spanish landlord or lender and you are quoting a number that appears on none of your payslips; quote the instalment as your monthly income and you understate your salary by a seventh.
On overtime, Spain sets a floor rather than a premium: an overtime hour must be paid at no less than the ordinary rate, or given back as time off. Article 35 of the Estatuto de los Trabajadores leaves that choice to the collective agreement or the contract, and gives the hours back as rest where neither settles it. The annual limit is 80 overtime hours. Anything above the plain rate comes from the convenio colectivo covering your sector, so two people on the same salary in different industries can be paid quite differently for the same extra hour.
The ordinary week is capped at 40 hours averaged over the year rather than fixed week by week, which leaves room for seasonal jornada intensiva arrangements. Statutory leave is 30 calendar days, which works out at 22 working days on a five-day week, and there are fourteen public holidays, the highest count in Europe here.