Choosing the new method of payment for foreign contract tax

According to the Official Letter No. 2575 / TCT-CS dated 28/06/2018 on the contractor’s tax policy:

To avoid the foreign contractors declaring, paying the VAT and CIT inconsistencies for different contractor contracts, in Clause 5, Article 20 of the Circular No. 156/2013 / TT-BTC mentioned above, Foreign contractors must continue to pay tax according to the registered tax payment method, in which case they may choose to register the new method of tax payment (in principle, if they have not yet terminated the contract of the former contractor, when signing the house contract new contractors, foreign contractors will have to continue to pay taxes on the new contract under the method registered for the old contract to ensure uniformity)