The loss to be recognized can be calculated as follows:
1. Calculate the total fee for selling the receivables: $220,000 * 3% = $6,600.
2. Determine the retained portion: $220,000 * 8% = $17,600.
3. The estimated fair value of the retained portion is given as $15,000.
4. Calculate the loss: $17,600 - $15,000 = $2,600.
Therefore, the loss to be recognized is $2,600.