Should I change most of my money in my home country or in the destination country? baht to canadian dollars....change in thailand or canada

My normal advice is in this answer, which is to get a card without foreign exchange fees and take the cash out while you're over there. You'll generally get the best rate by far with this, and you don't have the safety issues of carrying round a week's worth of money in cash.

If you are going to be somewhere without access to ATMs, so you need to take cash (either your own currency to change, or pre-change into the destination one), then there are some general tips. Firstly, airports will often give a poor rate, as they have a captive market and an expensive location. Next up, make sure you know the real rate, and shop around. Be aware that "commission free" normally means a worse rate (they still want to make a profit!), so normally only makes sense for small transactions. For large ones, a commission plus a great rate is often better, but get a calculator out and check!

Before you go, check what rate your bank will offer you (it may be good, or it may be shocking, so know what the real exchange rate is). See what you can get online, but don't forget that will involve a postage fee and a wait! Then check with the post office, and if you live somewhere touristy, try a bureau de change near you. (Where I live, we have lots of american tourists, so you can often get a good rate if you want to buy USD, but rarely if you want to sell them!). Finally, try and check (either online or on the phone) what rate you can get at your destination.

It depends not on which country is your home but which country offers the best exchange rates.

Since you have not listed either where you live or where you're planning to go we can't give you more specific advice.

But here's some general advice.

Usually the richer a country is, the more expensive money changing is.

Developing countries often want major foreign currencies like USD and EUR and will offer better rates for them than you'll get buying the foreign currency of a developing country in the US or Europe (or Australia or Japan etc).

Places with a black market can sometimes offer even better than official exchange rates for the big currencies so the dodgy money changers on the corner can give better rates than the banks or official money changers. But as they're dodgy know your numbers and don't get scammed!

Another thing to keep in mind is "How exotic is the currency of my destination?" If you're going somewhere with a stable world currency like USD, GBP, EUR, AUD, JPY, etc you can change those pretty easily. If you want something a little more interesting like Albanian leks or Armenian dram you might not be able to change them at home at all but you will certainly be able to when you get there. Especially if your destination country has an expat community in your departure country.

This all of course assumes that you definitely want to phsyically change money. If in fact you really want to know the best way to deal with money issues while travelling, then Gagravarr's answer deals with that more general problem

It is much better to exchange monies in the country of visit but make sure you go to forex bureau as they always offer better rates compared to border money changers. Or ask your tour guide in the place of visit, in most cases they always know the offers and good prices.

I would observe the trend of the currency of the home country versus the foreign country's currency before making a decision.

If the currency of my home country (the dollar in my case) were falling, I would try to exchange it as soon as possible, which is to say before I leave home, to get more foreign currency for my dollars.

If the dollar seemed to be rising, I would exchange it as late as possible, meaning when I arrive in the foreign country. The main exception would be if the "spreads" around the basic exchange in the foreign country were much larger than in the U.S. Then I might do the currency exchange at home,or in a third country, even if I expected the dollar to rise against the foreign currency.

I dont know if this thread is still topical (probably always will be ?) but I'll give you my example of a 2014 currency transaction.

I live in the UK and I am travelling to Thailand in September 2014. At the time of writing XE.com tell me that the current exchange rate is 500.00 GBP = 26,267.37 THB

1. My bank and most other "High Street" foreign currency providers are offering me 25,500.00 THB for 515.00 GBP. Note that any amount smaller than £500 will attract a lesser rate.

2 A specialised Foreign Currency provider in the UK (in this case "Currency Exchange Corporation") can give me 25,520 THB for £500.05.

3. If I wait until I reach Bangkok, Bangkok Bank are offering 25,975.00 THB for £500.00

So taking into account that Thailand are keen to have foreign currency but not desparate it would appear that waiting until you reach the country is the best bet ?

An option not yet mentioned is to get a prepaid credit card in the destination currency before you travel.

You will not get hit by transfer rates as the card is billed in the same currency as the merchant bank plus as its a prepaid card were you to misplace it you are only risking what ever you put on the card.

The downside is some prepaid cards are not accepted everywhere. This depends on the type of card, and can be easily fixed by getting a secondary card from your current card network in a different currency.