Swiss tax return: 2026 guide in Aargau

Context

In brief

• Three levels: federal, cantonal and municipal.
• Each canton has its own law and multiplier.
• AFC/ESTV handles IFD and VAT.
• Indexed figures change every year.

Key facts

• Structure → 3 levels: IFD, cantonal, municipal
• Federal authority → AFC/ESTV: IFD and VAT
• Cantonal responsibility → cantonal administrations
• Municipality → multiplier on cantonal tax
• Statistics → UST/BFS, not tax rates
• Indexing → values to be checked every year

Three tax levels define the Swiss tax return: direct federal tax (IFD), cantonal tax and municipal tax. This is the starting point for anyone who must complete the 2026 tax return in the canton of Aargau and for anyone comparing the cantonal system with the national one.

AFC/ESTV is the federal authority responsible for IFD and VAT. Cantonal and municipal taxes, on the other hand, are administered by the cantonal administrations. The municipality enters the calculation through its own multiplier applied to cantonal tax. For this reason, when reading the return, the federal, cantonal and municipal levels must be kept distinct, even when the items appear in the same procedure.

What changes for those filing in Aargau

The cantonal element is not merely a formal detail. Each canton has its own law and its own multiplier; the 2026 procedure must therefore be read according to the instructions of the administration responsible for Aargau and for the municipality concerned. The deadline to be observed is the cantonal one associated with the 2026 return, without replacing it with a generic deadline.

The same distinction prevents responsibilities from being assigned incorrectly. UST/BFS produces statistics and does not set tax rates. UFAS/BSV concerns social security, including AVS/AHV, AI and LPP/BVG, but does not establish taxes. These distinctions are essential when moving from a payslip to the tax return.

For allowable deductions, the practical rule is to use only the rules associated with the return of the competent canton. The rules of another canton cannot be transferred automatically, because each canton has its own law. Values subject to annual indexation, such as the maximum for the third pillar 3a, the LPP coordination threshold or deduction, the AD/AC maximum, average LAMal premiums and the median salary, must also be checked for the correct year. Those about to complete the return can start from dichiarazione delle imposte, keeping the three levels separate.

Operational details

The national comparison should be made without looking for a single rate. The structure remains the same, but the law and the multiplier change from canton to canton. For those living in Aargau, this means that the first check is not a comparison with a generic number, but rather identifying the authority and municipality included in the tax return.

The table also serves to prevent a reading error: AFC/ESTV does not replace the cantonal administration for the cantonal and municipal components, while UST/BFS cannot be used as a source for tax rates. Statistical data and tax data have different functions.

Payslip, social insurance and health insurance fund

A second check concerns deductions from salary. AVS/AI/IPG account for 5,3% borne by the employee and 10,6% overall with the employer. AD/AC is 1,1% up to the annual maximum. LAINF/LAA varies from 0,7% to 1,5% depending on the sector. LPP/BVG, on the coordinated salary, provides for 7% between 25 and 34 years, 10% between 35 and 44, 15% between 45 and 54 and 18% from age 55 up to the reference age. These are contributions linked to salary and should not automatically be confused with the three levels of tax.

LAMal/KVG follows another logic: for residents it is mandatory and must be taken out within three months of arrival; the premium is per capita, not a tax or a salary contribution. Premiums depend on the canton and region, while premium reductions are a cantonal subsidy. Deductibles for adults are CHF 300, 500, 1000, 1500, 2000 or 2500. To separate these items more clearly, busta paga svizzera and the guide to LAMal e cassa malati can be used alongside the tax return.

The final caution concerns the reference year. Figures indexed each year are not interchangeable: the 3a maximum, LPP coordination, AD/AC maximum, average LAMal premiums and median salary require an updated verification.

Useful planning tools

To estimate your pension strategy, use the pension planner and the pillar 3 simulator.

Key points

For the 2026 online filing in Aargau, the process can be organized into five steps, without mixing up authorities and entries.

The operating procedure

1. Determine the tax scope. The tax return covers IFD, cantonal tax and municipal tax. It is necessary to identify the relevant canton and municipality, because the municipal multiplier is applied to the cantonal tax.

2. Select the correct authority. For IFD, the relevant authority is AFC/ESTV; for cantonal and municipal taxes, follow the cantonal administration. UST/BFS is the statistics agency, not the reference for looking up tax rates.

3. Check the cantonal deadline. The 2026 guide should be used together with the deadline established for the relevant canton. For Aargau, therefore, follow the cantonal instructions for the tax return, without carrying over dates or rules from another canton.

4. Check the deductions and annual values. Apply only the deductions allowed under the canton's rules. For each indexed amount, such as the 3a maximum, the threshold or LPP coordination deduction, the AD/AC maximum, average LAMal premiums and the median salary, use the reference for the correct year and not a value remembered from a previous tax year.

5. Complete the filing online and review the separation of the entries. The AVS/AI/IPG, AD/AC, LAINF/LAA and LPP/BVG withholdings belong to the wage contribution framework; LAMal is mandatory for residents, but its per-capita premium is neither a tax nor a wage contribution. This check reduces the risk of assigning an authority a responsibility it does not have.

A final check before submission

The checklist does not require inventing a tax rate: it requires respecting the combination of cantonal law, the municipal multiplier and the federal level. If you change cantons, you do not automatically carry the same approach with you, because each canton has its own law and multiplier. If you check a payslip before the tax return, it is still necessary to distinguish between social security, health insurance and taxes.

Consulting the online procedure must remain anchored to the competent administration. This is the most straightforward way to handle a tax return in Aargau without confusing AFC/ESTV, cantonal authorities, UFAS/BSV and UST/BFS. To turn these steps into a numerical check, use calcolatore stipendio/imposte.