Form 353 - Technical assistance

The online filing of form 353 requires identification with the electronic certificate of the taxpayer.In addition to the holder of the tax return themselves, a third party acting on their behalf, either a corporate partner or a proxy, may also submit the tax return.

After you identify yourself, you will be taken to the form.Please fill in the relevant data.

The group number field supports the following formats:

• VATxxxx/yy (VAT – 4 digits – bar – two year digits):example VAT0006/20

• xxxx/aaBVA (Four digits – bar – two year digits – letter B – letters VA):example 0006/20BVA

• xxxx/aaAVA (Four digits – bar – two year digits – letter A – letters VA):example 0006/20AVA

• xxxx/aaGVA (Four digits – bar – two year digits – letter G – letters VA):example 0006/20GVA

• 31xxxxx (Code 31 – five digits):example 3100006

Any other format returns the following warning:

Assessment results are automatically filled depending on the data provided in the other fields.In addition, with this form you can file a supplementary tax return with the same concept, financial year and period.In this case, the receipt number of the previous tax return must be indicated.

In the "Group entities paying tax in the special system” section you will find buttons to register, cancel and browse through the records.To register a record, click on the "New record" icon, identified by a blank sheet of paper with a green "+" sign.Fill in the NIF of the dependent entity and the rest of the boxes.

From the lower button panel, it is possible to access the functions for validating the tax return, saving and loading data, importing and exporting files and processing the payment/return.

Before filing the return, it is advisable to check for any warnings or errors, by clicking on the button "Validate return" a section will open with the errors and warnings detected.Click on "Go to warning" or "Go to error" to access the field or section to be reviewed.

Remember that notices are informative and do not prevent submission.However, the errors must be corrected.

At any time, even if there are errors or the declaration has not been completed, the data entered may be saved so that they are stored on the server of the AEAT, by clicking on the button "Save".Subsequently, they can be retrieved by clicking on the button "Load", to continue filling them in.

If there are no errors, you can "Export" a file with the tax return in the valid BOE format (extension .353) for filing.The "Import" button allows you to incorporate a file with the tax return in BOE format, exported from the same form or generated from an external program following the specifications of the published registry design.

Once the return is complete and validated without errors, click "Process Payment/Return" to file.

Select the type of declaration according to its result.If the result is an amount payable, the field will be enabled to include the NRC Reference Number, a 22-character code that serves as proof of payment.The payment can be made previously or at that moment, from the link "Optional:Obtain NRC", which will link to the payment gateway to make the payment with the data provided in the form.

If the result is negative, enter the IBAN account of which you are the account holder or apply for a refund on an account opened abroad (EU/SEPA).

Click on "Sign and send", in the next window check "OK" and click "Sign and send".If everything is correct, you will get a reply sheet with the message "Your filing was successful".The incrusted PDF has a first page with information regarding the submission (record entry number, Secure Verification Code, receipt number, date and time of submission and the details of the person who submitted the tax return) and, on the following pages, a full copy of the tax return.