Do I need onward travel plans when entering Thailand on a METV?

No onward ticket, no METV. You didn't check it nor applied yet I assume.

A multi entry Tourist Visa can only be applied for in your home country, i.e. the country of your residence.

Recent reports indicate that the Thai embassies in Laos and Vietnam allowed tourists to apply for the METV without the need to be residents.

A multi entry Tourist Visa has a validity for use for an unlimited number of entries (“multiple entry”) during its 6-month validity.

The 6 months visa validity starts on the day the visa is issued. Thus, if you enter Thailand 9 days after it has been issued, you lose 9 days of the total of the 6 months visa validity.

PLEASE don’t confuse the date of expiry of the visa validity, with the date of expiry of the stay permit. These are two different dates!

Be aware that if applying for the METV through the E-visa online system, you will need to show proof of why you need a METV over a SETV (single entry 60-days Tourist visa)

This proof could be like a flight ticket out of Thailand to a neighbor country within the first 60 days, and a flight back home within 6 months, at least. If the processing embassy or consulate are not convinced, they may issue a SETV and won’t refund the difference in the application fee.

Many embassies have started to ask for a proof of funds for the application to the METV. It is like three months of account statements that prove you have at least savings of a minimum of 20,000 THB equivalent in your currency.

*** On each entry, you will get stamped in for a 60-days stay permit

On each and every 60 days stay permit, you can apply for a 30-days touristic extension of the stay permit, for 1900.- THB, on Immigration. You could, however, also make a border run instead, before the expiry of the 60-days stay permit.

If you take the 30-days extension, you must be aware that before the 90th day expires, you need to exit Thailand.

*** With the next entry, you will activate another 60-days stay permit

Which you also can extend for 30 more days.

To get the maximum number of days out of this visa, you should therefore enter Thailand as close as you can, to the date of issue

If you exit and re-enter Thailand as close as possible before the visa validity expires, you will get stamped in for 60 days for the last time.

You can then still get a 30 days extension of this last 60-days stay permit.

By this method, you can theoretically get almost 9 months of stay in Thailand out of the multi entry tourist visa.

WARNING: some recent reports have indicated that holders of the METV got refused a last 60 days stay permit upon the individual discretion of the Immigration officer at the border.

This means that the road to a 9-months stay could be blocked.

So please BEWARE: take into account that your actual stay maybe cannot extend 180 days.

If you come from Europe or the U.S. the airline might ask for it, but if you come from the neighboring countries - most likely not.

Yes you need an inbound ticket from your home country , an exit ticket from Thailand an a second inbound air ticket in order to successfully apply for the METV.

Ask your airline

Yes

I've personally been to Thailand 15 times in one way tickets. Only actually got asked one time and it was the airline not immigration Emirates They still let me go anyway . If you ever over stayed a visa you will be flagged and Thai immigration will ask you for proof but if you been multiple times and not over stay you won't have an issue

Yes u do

You need onward travel plans when applying for the METV