Stamp duty on sales contracts needs to be declared in 9 steps, as follows:

1. Open the electronic tax bureau and choose to declare tax.

2. Select consolidated tax returns for property and behavior taxes.

3. Choose stamp duty.

4. Click Add.

5. Select the sales contract for tax items.

6. Enter the tax amount and click OK.

7. Click Save.

8. Check the saved records, and then click Next.

9. The system generates a stamp duty tax return, and click Declare to complete the operation.