it appears your spouse is working regularly in your business so the question is how many hours does she work. there is no bright line in these circumstances and if she's participating materially in the operations you really have a partnership. Say she is not materially participating and you treat her as an independent contractor. If she puts in too many hours (no specific number can be offered) the IRS could reclassify her as an employee. in that case you would be hit with substantial penalties and interest
if you were to treat her as an IC you will likely on a joint return end up paying the same taxes as if you did not pay her at all. (as an IC she would be paying the self-employment taxes that you are not paying due to the deduction for her compensation). the advantage of paying her as an IC or possibly treating her as a partner is she builds up her own social security credits and can contribute to a retirement plan.
NOTE:
Business owned and operated by spouses. Generally, if you and your spouse jointly own and operate an unincorporated business and share in the profits and losses, you are partners in a partnership and you must file Form 1065.
