For messenger fees, if the invoice include the messenger fee to calculate VAT, need to deduct 3% WHT?

Panwa: yes, for messenger fee, you need to deducted WHT 3%.

For more information, please feel free to contact us:
Phone : +66 2 933 9000
Fax: +66 2 933 6120
Email: bkk@panwa.co.th

For more information, please feel free to contact us:

Office: +66 2 933 9000
Whats'App: +66 8 5713 1000
Email: bkk@panwa.co.th

Location: https://goo.gl/maps/MhJsbjkPrji51Qyt6
Sky train: Yellow Line, Chokchai 4 Station, Gate 4. Our office is located between Soi Latphrao 50 and 52.

Address: 1560 Latphrao Road, Wangthonglang, Bangkok 10310, Thailand.