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# How is the deductible interest charge prorated?

###### For the 2024 tax year: 

No prorata calculation is made for the 2024 tax year. 


###### For the 2023 tax year: 

The calculation of deductible interest expense is based on a number of factors, including : 
* the date of acquisition of the property
* the date on which you moved into the property 
* the interest paid on the mortgage
* the interest ceiling. 

### Here are 2 examples:


| Example 1:
A couple (married or civil union) bought a house on 01/04/2023 and moved in on 01/07/2023. 
They paid interest of €10'000 in 2023.
The ceiling to be applied is €6'000. 
Non-occupancy period: 91 days
Days to end of year: 275

---

### Calculation details :

Field 1017: __
10'000 * (91 / 275) = 3'309,09€

Field 1021: __
10'000 - 3'309,09 = 6'690,91€
As the €6'690.91 is greater than the €6'000 ceiling, the ceiling must be applied.

Field 1029: __
3'309,09 + 6'000 = 9'309,09€

---

![](https://storage.crisp.chat/users/helpdesk/website/1c5fc819171ffd00/image_o1mftf.png)


| Example 2 : 

A single person bought a house on 01/04/2023 and moved in on 01/07/2023. 
He paid interest of €5'000 in 2023.
The ceiling to be applied is €3'000. 

Non-occupancy period: 91 days
Days to end of year: 275

---

### Calculation details :

Field 1017: __
5'000 * (91 / 275) = 1’654,55€

Field 1021: __
5'000 - 1’654,55€ = 3'345,45€
As the 3'345,45€ is greater than the €3'000 ceiling, the ceiling must be applied.

Field 1029: __
1’654,55 + 3'000 = 4'654,55€

---

![](https://storage.crisp.chat/users/helpdesk/website/1c5fc819171ffd00/image_iowep5.png)