You are better off bringing with you all the money you will need (even to Mali in general). Bring it in cash, large denomination bills preferably in Euro. For a list of banks in Timbuktu their locations and hours see below

Travellers checks
are complicated. Even banks don’t like to deal with them. The BNDA (Banque National D’Agriculture) and BIM (Banque International du Mali) will change them. You should have your receipts of purchase with you (be sure to carry them separately from the traveler’s cheques--you aren’t supposed to have to present these as there are only incase of loss or theft but... banks here are complicated and may ask for this proof) If the cashier is unable to help you ask to see the director of the bank, he at least should know what to do.

In Timbuktu the BNDA is the only bank in Timbuktu that can change US dollars if it is in $20, $50 or $100 bills. The exchange rates fluctuate and are never very good. Even in Bamako only the ECO bank changes USD and usually only $20 or higher denomination bills of the newest variety that means the ones with the big heads AND colour added. At the “black market” shops on the street that change money the rate may or may not be better but will give you a lesser rate for $20's than for $50's or $100's.

is easily changeable at the BNDA, BIM, or BDM banks or in many shops around the market. Hotels will likely accept payment in euro if you are low on CFA. The official exchange rate at the bank is 655 CFA to the €. Most shops will give you 650 even. This amounts to 500 francs less per 100€, which seems hardly worth the bother of going all the way down to the bank and waiting in line especially since the banks will take a commission that at least equals the difference in the rates.

All Other Currencies
It is basically impossible to change currencies other than USD and Euro in Mali unless you find other travellers willing to trade.

Cash Advances
At the BDM (Banque de Developement du Mali) and the, you can sometimes get cash advances on VISA card. I have never heard about MasterCard or American Express being used in West Africa. The advance works with varying degrees of success, though it is supposed to have improved recently. Expect to spend a long time at the bank. If the tellers are having trouble ask to speak with the director.

Cash Machine (ATM) One has been installed in at the BDM, the BIM and the BMS where you should be able to withdraw cash directly from your VISA card. It has a separate entry from the bank so that you can access it even if the bank is closed. Many visiters have sucessfully withdrawn cash from this machine. There have been times when travellers have found the machine empty of cash and have had to wait until the bank refilled it to withdraw funds. Some other visitors have complained of limits on the amount permitted to be withdrawn a time. I do not know enough about these machines to know if this is normal, a condition of certain banks or, a problem with the machine. I have no experience of the fees charged for such transactions, ask your bank or VISA provider for more information.

PLEASE NOTE: Let your bank know when you are planning to travel out of your home country. A list of the countries you intend to visit and the general time frame should be included. Many banks will block transactions on a credit card that is in an unexpected place.

Wiring money
The BDM and BIM have Western Union money transfer that is easy and fast. The person sending the money needs your full name as it appears on the ID you will be presenting to collect. Then needs to let you know the 10 digit code and a test question/answer. Money will be paid out in CFA. The BNDA and BMS have MoneyGram. The procedures are basically the same. There are fees involved for the sender only. On Saturdays BDM is open from 8h00 until 11h30 for western union and BIM from 9h00 to 11h30 and 13h15 to 16h00.

Credit Cards
To my knowledge NO business in Timbuktu has the capacity to take payment by credit card.

There are five Banks in Timbuktu as follows:
BDM - Banque de Developement du Mali Located on the road heading south out of town on the pavemement known as the Route de Kabara past the Stadium. There is a big sign white with blue lettering on the east side of the road (left if you are coming from town). Hours are: Monday - Thurday: Friday: Saturday open for Western Union only 8 am to 11h30

BHM Banque de l’Habitat du Mali In the same building as the post office From the place d’independance go south on the Route de Kabara on the east side of the road past the City Hall and the SOTELMA offices. It is the last building before the paved road that goes east towards the hospital etc. It does not offer services usefull to tourists.

BIM Banque International du Mali also known as AlWafiya. South of town on the route de Kabara past the BDM on the west side of the road it has a huge sign in red and yellow; the tall plastic kind that can be lit up inside. Its hours are Monday to Thrudsay 7h30-11h30 and 13h15-15h00; Friday 7h30 -11h30; Satuday 9h00 - 12h00. It is open for western union only for longer hours Mon-Thursday untill 17h30, Friday afternoons from 13h15-15h00 and Satudays untill 12h30 in the morning and untill 16h00 in the afternoon.

BMS Banque Malian de Solidarite Located just a little ways south of the Maison des Artisans or just north of the Hotel Columbe. It has a cash machine in the south end and does money gram transfers

BNDA Banque National D’Agriculture The farthest bank south on the Route de Kabara past the BHM, BDM and BIM and keep going. It is on the east side of the road and you have passed it if you get to the LybiaGas fuel station the signs are green on white It is the only bank that changes US dollars and it does money gram transfers. It may also have recently installed a cash machine but I have yet to confirm this.