You can send Form 9465 with the e-return, but the IRS must still approve the installment agreement form.
Form 9465 can be included electronically with an e-filed return or paper-filed. When filing a paper return, complete Form 9465, attach it to the front of your client's return before mailing. They should receive a response to the request for installment payments within 30 days.
If you mail Form 9465, the IRS will respond to your request typically within 30 days but it may take longer during filing season. Installment agreements by direct debit and payroll deduction enable you to make timely payments automatically and reduce the possibility of default.
About Form 9465, Installment Agreement Request. Internal Revenue Service.
IRS Form 2159, Payroll Deduction Agreement, is a tax document to set up an installment agreement, a form of tax debt relief that allows taxpayers to make monthly payments on their federal tax debt by having funds withheld from their paychecks and sent directly to the IRS.
If you don't qualify for an IA through OPA, you may also request an IA by submitting Form 9465, Installment Agreement Request, with the IRS. When you request an IA using the form, generally, you'll receive a response from the IRS within 30 days notifying you of whether the IA request was approved or rejected.