Question 1

Is the HOAI still binding?

Accepted Answer

Only partly. On 4 July 2019 (C-377/17), the European Court of Justice ruled that the binding minimum and maximum rates of HOAI 2013 breached the EU Services Directive. Since HOAI 2021 (in force from 1 January 2021) the fee tables are guide values only (§ 2a HOAI). The fee is freely negotiable but must be agreed in text form. Without such an agreement, the base rate is deemed agreed (§ 7(1) HOAI). The service descriptions and definitions remain in force.

Question 2

How is the architect fee calculated under the HOAI?

Accepted Answer

In four steps: 1. Determine the eligible costs (net construction costs from the cost calculation or estimate). 2. Assign fee zone I to V. 3. Read the table value from § 35 HOAI and interpolate linearly between table steps (§ 13); within the zone the fee lies between the base rate and the upper rate. 4. Multiply the result by the percentages of the commissioned work stages (§ 34). Add any refurbishment surcharge, expenses and 19% VAT.

Question 3

How much is the architect fee for a single-family house?

Accepted Answer

According to the object list (Annex 10.2 HOAI), single-family houses fall into fee zone III or IV. At €500,000 eligible costs in zone III, the table for all nine work stages ranges from €62,900 (base rate) to €78,449 (upper rate) net, roughly 12.6 to 15.7% of construction costs. With 5% expenses and 19% VAT, the base rate comes to about €78,600 gross. Actual quotes may differ.

Question 4

What are eligible costs?

Accepted Answer

Eligible costs are the part of the construction costs on which the fee is based (§ 4 HOAI). For buildings this is mainly the full cost of the building structure (cost group 300 under DIN 276) plus the technical systems (cost group 400) on a pro-rata basis under § 33 HOAI. VAT is excluded. Land, site development and ancillary construction costs usually do not count either. The cost calculation is decisive, or the cost estimate if there is none.

Question 5

Which fee zone applies to my project?

Accepted Answer

The fee zone depends on how difficult the design is. For buildings six criteria count: integration into the surroundings, number of functional areas, design and structural requirements, technical systems and fit-out (§ 35(2) HOAI). Annex 10.2 lists typical cases: carports zone I, simple garages zone II, single-family houses zone III to IV, universities zone IV, university hospitals zone V. In case of doubt, points are awarded: up to 10 points zone I, 11–18 zone II, 19–26 zone III, 27–34 zone IV, 35–42 zone V.

Question 6

How high is the refurbishment surcharge under the HOAI?

Accepted Answer

For conversions and modernisations of buildings of average difficulty, a surcharge of up to 33% on the fee can be agreed, for interiors up to 50% (§ 36 HOAI). If nothing is agreed in text form, a surcharge of 20% is deemed agreed from average difficulty (§ 6(2) HOAI). Separately, existing building fabric that is incorporated can increase the eligible costs (§ 4(3)).

Question 7

What expenses may the architect charge?

Accepted Answer

Under § 14 HOAI, for example postage and data transmission, copies, a site office, travel beyond 15 km from the office and fees for services passed to third parties. Expenses are charged individually unless a flat rate has been agreed in text form. In practice, flat rates of around 3 to 6% of the fee are common. Reimbursement can also be excluded entirely by contract.

Question 8

Is there a new HOAI coming in 2026?

Accepted Answer

A reform has been announced politically. Reports commissioned by the Federal Ministry for Economic Affairs recommend considerably higher table values. As of 24 September 2026, however, there is neither a draft bill nor a cabinet decision, and the ordinance also needs the consent of the Bundesrat. HOAI 2021, last amended on 22 March 2023, therefore still applies. We will update the calculator as soon as a new version is adopted.

Guide: HOAI Fee Calculator

Calculating Architect Fees in Germany: How HOAI 2021 Works Step by Step

HOAI Work Stages 1 to 9: What the Architect Delivers in Each Stage

Determining the HOAI Fee Zone: Object List, Points and Examples

Eligible Costs under the HOAI: What Counts, What Doesn't and How to Calculate

HOAI Refurbishment Surcharge: 20, 33 or 50 Per Cent and Existing Building Fabric

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