4 minutes ago, z909 said:

The time to get to Silom will depend on what time of day you arrive, the day of the week and how long you have to wait for your train or taxi.  The traffic around Silom can now be virtually at gridlock in early evening.     Not a problem as I take the train and MRT.

As for change, well when leaving Thailand, I never change any baht back into my own currency, so I always have some small notes for buying the public transport tickets, plus larger notes just in case of unexpected problems.

 

 

OP is landing 22 00 pm so traffic will be over.

In case  one doesn't  not have a change for Taxi/ train there are tons of  7/24 open exchange booths where 20-30 GBP/ EUR/ USD/ you name it / can be exchanged to fund our trip do the city. 

Rates are worse than on the streets but not dramatically so and on such small amount one will not lose that much, perhaps 10-12 % . Also rates are uniform throughout the airport so no need to hunt for the best.

Of course exchange booths at airport train station are offering close to best rates everywhere ( in October last year  I got the positively best rate for my currency there ,  better than anywhere in BKK and PTT ) but they close before midnight so for late comers are of no use unless somebody is thrifty type who wants to camp there till morning to obtain such good rate, LOL

If you plan to return to Thailand you may find that it’s a good practice to retain sufficient local currency to cover your anticipated spending on first night of next trip. Once less hassle on arrival when you have other priorities. 

If you plan to use travelers checks, fewer banks seem to be accepting them. In Silom Complex, Siam Commercial Bank (SCB) still does but the agent specified American Express. 

Consistently i find that SuperRich provides the best currency exchange rate. The location on Silom (near Arena masssage) May be slightly better than Silom Complex location but probably not worth going out of your way on a steamy day. Silom Complex branch closes at 8p.m.

Also note that after about 9p..m., the rates at independent currency exchange booths along Silom and Surawong become less favorable.