@Mathieu ****
"Even if your net tax due is zero, you are still legally required to submit a tax declaration (Form P.N.D. 90) if your remitted foreign income exceeds the standard Thai filing thresholds.
If you do not declare it and the Thai Revenue Department audits you:
• The 2,000 Baht Penalty: You can be fined up to 2,000 Baht strictly for the administrative failure of not submitting the tax form.
• No Evasion/Surcharge Fines (If Tax Owed is Zero): Because the 200% audit penalty and the 1.5% monthly surcharges are calculated as percentages of unpaid tax, if your Swedish tax credit reduces your Thai tax bill to zero, the 200% penalty and monthly surcharges equal zero. You cannot be heavily fined for evading a tax bill that technically amounts to nothing." (This is for my specific case, your country of origin may differ and the rules aswell).