Advantages for Merchants

Taler is a cost-effective electronic payment system which provides you with cryptographic proof that the payment worked correctly within milliseconds. Your Web customers pay with previously unknown levels of convenience without risk of fraud.


Processing transactions with Taler is fast, allowing you to confirm the transaction with your customer virtually immediately. Your customers will appreciate that they do not have to type in credit card information and play the "verified by" game. By making payments significantly more convenient for your customers, you may be able to use Taler for small transactions that would not work with credit card payments due to the mental overhead for customers.


You will have cryptographic proof of payment from the Taler payment service provider. Taler does not require you to undergo any particular security audits (such as PCI DSS), processes or procedures, as you never handle sensitive customer account information. Your systems will have customer contracts wih qualified signatures for all transactions which you can use in court in case of disputes.

Free Software

Taler is free software, and you can use the liberally-licensed reference code as a starting point to integrate Taler into your services. To use Taler, you do not need to pay license fees, and the free software development model will ensure that you can select from many competent integrators for support.

Low Fees

Taler is designed to minimize the work the exchange needs to perform. Combined with Taler's strong security which prevents fraud, payment service providers can operate with very low overhead and thus low transaction fees.


Taler can be used for different currencies (such as Euros, US Dollars or Bitcoins) and different payment models limited only by what the payment service provider supports in its interactions.


Taler prevents tax evasion and money laundering. Taler's protocols are efficient and do not waste energy. Taler encourages transparency by providing an open standard and free software reference implementations.

Taler as seen by merchants

Merchants supporting the Taler system need to integrate some relatively simple logic into their transaction processing system. Typical steps performed by the merchant system are:

merchant perspective

  1. The new logic detects when a customer's system supports Taler and then needs to send a cryptographically signed version of the proposed contract in a simple JSON format to the customer. The message also includes salted, hashed wire details for the merchant, as well as restrictions as to which exchange operators the merchant is willing to deal with.
  2. The customer sends a signed response which states that certain digital coins now belong to the merchant to both signal acceptance of the deal as well as to pay the respective amount (bottom).
  3. The merchant then forwards the signed messages received from the customer to the exchange, together with its wire details and the salt (without hashing). The exchange verifies the details and sends a signed confirmation (or an error message) to the merchant. The merchant checks that the exchange's signature is valid, sends a confirmation to the customer and executes the contract-specific business logic.
  4. The exchange performs wire transfers corresponding to the claims deposited by the merchant. Note that the exchange may charge fees for the deposit operation, hence merchants may impose limits restricting the set of exchange operators they are willing to deal with, for example by imposing a bound on deposit fees.

Manuals for merchants