iStockphoto has announced today it now offers Subscription plans and Corporate Accounts in addition to its micropayment Pay-as-you-go credit system. Subscribers can access the same royalty-free content as Pay-as-you-go customers: photos, illustrations, video and Flash files. Beginning this September, audio tracks will be available to subscribers, offering customers a complete palette of multimedia tools.

Subscription plans give clients a daily credit limit to be used in three, six or 12-month time periods. Plans range from 10 to 480 credits per day and start as low as £55. Clients can use a subscription calculator to customise the best subscription to suit their needs based on the number of credits required per day and the total time period of the plan.

iStockphoto also recently added Corporate Accounts which are fully-loaded with greater management and reporting features. A Corporate Account Administrator can create Sub-Accounts, set credit limits for the Sub-Accounts and easily manage the account with customisable reporting tools.

iStockphoto says that it guarantees that artists will never earn less per credit than they do under the original Pay-as-you-go system. Each Subscription or Corporate Account download still counts as a normal download towards iStock artists’ canister levels. iStock’s royalty structure for Subscription downloads uses a straightforward formula. Each subscriber has a daily credit limit. iStock will apply each artist’s standard canister royalty as a percentage of that daily limit which was used to download the particular image.