Is the HOAI still binding?

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.

How is the architect fee calculated under the HOAI?

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.

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

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.

What are eligible costs?

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.

Which fee zone applies to my project?

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.

How high is the refurbishment surcharge under the HOAI?

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)).

What expenses may the architect charge?

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.

Is there a new HOAI coming in 2026?

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.

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

Nine stages from the first meeting to the end of the warranty period

The HOAI divides the architect's work into nine work stages (Leistungsphasen). Each stage carries a fixed share of the fee (§ 34(3) HOAI) and includes specific basic services listed in Annex 10.1. Knowing the stages helps you understand what you are paying for and lets you commission individual stages. In the HOAI fee calculator you can switch each stage on or off.

Stage 1: Basic evaluation (2%)

The architect clarifies the brief with you: room schedule, budget, timeline, site and legal framework. They advise on further needs, for example whether structural or building services engineers are required. The result is a shared basis for the design.

Stage 2: Preliminary design (7%)

The first sketches and options are produced. The architect develops a design concept, checks it against building law, holds initial talks with authorities and prepares the cost estimate under DIN 276. This estimate serves as a provisional basis for your financing.

Stage 3: Final design (15%)

The chosen concept becomes a fully worked-out design, usually at a scale of 1:100. Structure, building services and materials are integrated. The stage ends with the cost calculation, which is normally the final basis for the fee. The final design is the point at which the form of the building is fixed.

Stage 4: Planning permission (3%)

The architect prepares the planning documents and submits the building application. They follow the procedure until permission is granted and supply additional documents if the authority asks. For interiors this stage is worth 2%, because permission is often not required.

Stage 5: Construction documents (25%)

The construction documents translate the design into working and detail drawings at scales from 1:50 to 1:1, from which the trades build. At 25% for buildings and 30% for interiors, it is the second-largest stage. Mistakes here become expensive on site, so careful commissioning pays off.

Stage 6: Preparing the tender (10%)

The architect determines quantities and prepares the bills of quantities used to obtain bids from contractors. A schedule is drawn up and the cost calculation is compared with the priced bills of quantities.

Stage 7: Assisting with the award (4%)

Bids are obtained, checked, compared and negotiated. The architect prepares a price comparison, recommends awards and assists in placing the contracts. They compare the costs with the results of the award so that you spot deviations early.

Stage 8: Site supervision (32%)

The largest stage: the architect checks that construction matches the permit, drawings and contracts, coordinates the trades, keeps the site diary, checks invoices, tracks costs and deadlines and organises acceptance. Because of the time spent on site it is worth 32%.

Stage 9: Post-completion support (2%)

After handover, the architect assesses defects found within the limitation periods, for at most five years from acceptance. Before the periods expire, they inspect the building to identify defects and assist in releasing retention securities. Supervising the remedy of defects, on the other hand, is a special service and must be agreed separately.

Partial commissioning: what is allowed?

You do not have to commission all stages at once. Under § 8(1) HOAI, only the percentages of the commissioned stages may then be charged. Commissioning in steps is common: stages 1 to 4 first (27% for buildings), then stages 5 to 9 after planning permission. If only some basic services within a stage are commissioned, only the corresponding share is payable (§ 8(2)).

At €400,000 eligible costs in zone III at the middle rate, stages 1 to 4 together come to about €15,606 net and stages 5 to 9 to about €42,193. The HOAI fee calculator shows the exact value for your project in the bar chart per work stage.

Conclusion

The work stages make the architect's fee transparent. Almost 60% of the fee goes on construction documents and site supervision; cutting here is often a false economy. The main article Calculating architect fees in Germany explains how the stages feed into the overall calculation.

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