@Vernon ********
For a day trip, no. You do need to purchase a "day pass" or "2 week pass", either in THB or USD though. Each border has different rules but the price is generally always 500 Baht or USD 10.
Technically (pre-Covid, when the border was open), expats have been permitted to travel to Dawei, on the Andaman coast without a visa if using the Phu Nam Ron crossing for a stay not exceeding 2 weeks upon payment of a 500 Baht or USD 10 fee. Very few took advantage of this, as most arrived with a visa, which would allow you to travel around the country (except for restricted areas).
The Mae Sai/Tachilek border also allows visa-free visits for up to 14 days as far north as Kengtung, 160km north or occasionally even the Chinese border town of Mongla, 68km further on. However, Tachilek immigration retains your passport and you'd be required to come back the same way.
The Ranong/Kawthoung border allowed a 14 day stay, whereby you could visit several of the nearby islands in addition to Kawthoung and surrounding areas.
Mae Sot/Myawaddy only ever allowed a one day stay. For overnight stays, a visa or e-visa would be required.
E-visas, valid for entry at 3 out of the 4 checkpoints and exits at any of the 4, was an alternative to getting an embassy issued visa.