You can legally pay rent to your wife even if she is a joint owner of the property. The only thing to note is that she can receive rent only for the portion of the property she owns. For example, if your wife owns 50% of the property rights, then she can only receive 50% of the total market rent rate for that property. Note that even though you are claiming HRA benefit using this technique, it is really difficult to prove it to the Income-tax auditor if they decide to check your case. Normally, your employer may also not approve your HRA tax exemption claim if you cannot produce rent receipts along with your PAN number.