What is a “Cost & Necessity” Affidavit in Texas?
In Texas, a “cost & necessity” affidavit is used in the litigation process as evidence of expenses or damages incurred in a civil suit. The use of this affidavit is governed under Texas Civil Practice and Remedies Code, Chapter 18. It is routinely referred to by Texas lawyers as a “billing affidavit.” In personal injury cases, these affidavits are most commonly used for proving the amount of medical expenses incurred by the injured party. Since I have been practicing in the field of personal injury in Texas since 1994, this article will, therefore, concentrate on how these affidavits are used in a typical personal injury case.
Medical expenses must be “reasonable.”
Reasonable, Usual & Customary Charges.
Under Texas law, in order to collect damages for medical expenses, there must be proof that the medical expenses are “reasonable.” Put another way, the medical expenses must be the “reasonable, usual and customary” charges. For instance, if you were injured in a car wreck and taken to a hospital for treatment, you will want to collect the medical expenses incurred for your hospital visit from the responsible party. But, it is not enough to just enter your billing statement into evidence. You must also have proof that the charges are the “reasonable, usual and customary” charges for the services at the time, and in the area, where the charges were incurred. Medical Treatment must also be “necessary.”
Medical treatment must also be “necessary.”
In addition to showing that the charges are reasonable, you also have to prove that the treatment was “necessary.” The law does not just assume that the treatment you received at the hospital was necessary. Rather, the party wanting to collect damages for medical expenses must also present some evidence that the treatment for your injuries was necessary.
How do I Prove “Reasonable” and “Necessary” Treatment?
Naturally, the injured party is not qualified to testify that the medical expenses are reasonable. You have to be experienced in the field of medical billing in order to provide that sort of testimony.
Additionally, you are not qualified to testify that the medical treatment was necessary. You have to be a qualified physician or medical professional to provide that testimony.
So, in addition to having your billing statement and medical records entered into evidence, you must also have evidence from a qualified medical billing professional and/or doctor that the charges are reasonable and the treatment was necessary.
Naturally, this type of testimony will come from witnesses qualified to give such testimony. But good luck getting a billing professional or physician to show up at your trial and give you that testimony. You will have to issue subpoenas and hope that these people will be give you the testimony you need. Otherwise, you can make advance arrangements to have these witnesses appear at trial. But be prepared to pay the doctor a handsome amount for their time and effort.
Texas Civil Practice & Remedies Code, Chapter 18.
Obviously, calling a medical billing professional and a doctor to testify at each and every personal injury case is unduly burdensome not only to the parties in the case, but to the medical profession as well. Doctors would be inundated with subpoenas to appear at court and will barely have time to care for patients.
Therefore, Texas has in place a procedure where a party may use an affidavit to provide the required evidence of “reasonable and necessary.” This procedure is set forth in Texas Civil Practice and Remedies Code, Chapter 18.
How the “Cost & Necessity” Affidavit works in Texas.
Section 18.002 provides the form of the affidavits that may be used in lieu of calling live witnesses. The most common procedure is simply to have the custodian of billing records execute the affidavit and attach an itemized billing statement as part of the affidavit. Once that is done, then the affidavit along with the attached billing statement will provide the necessary proof to support an award of those medical expenses.
If you have more than one medical bill, then you must get an affidavit for each provider. For instance, If you go to the hospital and later have an MRI or physical therapy, then you need to get separate affidavits for the hospital bill, MRI, and physical therapy.
Procedure for Using the Affidavit.
Once you get the affidavit back from the provider’s billing custodian, there are certain procedures and deadlines before you can actually use them at trial. it is not enough to just bring the affidavits to trial for the first time.
Service and Notice Requirements of the Affidavits.
In order to use the affidavits at trial to prove your medical expenses, you have to serve them on all the other parties (or their attorneys). You must also file a notice with the court that you have complied with the service requirement. The notice must identify the affidavits being served. However, the affidavit itself is not filed with the court.
Once the affidavit is served on all other parties and the required notice filed with the court, then the affidavits may be used at trial.
Time Deadlines for the Affidavits and Notice Requirements.
The affidavits must be served by a specific time deadline. Generally, serving the affidavits and filing the notice with the court, must be done no later than 90 days after the defendant files an answer to the lawsuit. This deadline may be enlarged by the court for good cause shown.
Also, the deadlines may be different when the plaintiff is still under treatment with a provider.
The Effect of the Affidavit.
One you have obtained the affidavit in the proper form, served it on the other parties, and filed your notice with the court, the affidavit may be used to support an award of the medical expenses reflected in the affidavit.
However, the judge or jury is not required to make such an award. In other words, the affidavit only provides evidentiary support for an award of the medical expenses. The award of the medical expenses not automatic or mandatory.
The Controverting Affidavit.
What is a “controverting affidavit?” Sometime referred to as a “counter affidavit,” this is an affidavit used by the opposing party to negate the plaintiff’s affidavit. If a defendant wishes to controvert the reasonableness of the medical charges or the necessity of the treatment, the defendant must serve a controverting affidavit. Without a counter affidavit the defendant is not permitted to introduce evidence to controvert the reasonableness of the charges or the necessity of the medical treatment.
If an opposing party uses a counter affidavit, then the plaintiff’s affidavit can no longer be use as evidence for the medical expenses. You must now consider calling a witness at trial or taking depositions to provide the evidence needed to support an award of medical expenses.
Counter affidavits are not encouraged under the rule. In fact, Section 18.001 is more stringent on what is required for a counter affidavit to be valid.
Shorter Time Deadlines.
Unlike a billing affidavit, a counter-affidavit must be filed within 120 days after filing of the defendant’s answer. On its face, this sound like there is more time to file a counter affidavit. But, in actuality, it’s shorter.
A counter affidavit is not used unless the plaintiff first invokes the use the affidavit process. If the plaintiff serves affidavits on the 90th day after the answer, then the defendant only has 30 days to serve a counter affidavit. So, while the plaintiff has 90 days to prepare and serve the affidavits, the defendant has only 30 days after that to prepare and serve a counter affidavit.
Counter affidavit must be made by a qualified expert.
A plaintiff may have their affidavit done by the custodian of billing records. However, the counter affidavit must be completed by someone with sufficient skill, knowledge, education and experience to controvert the plaintiff’s affidavit. For instance, if the defendant believes that the hospital is overcharging, then the defendant must consult with, and retain, a medical billing expert who is experienced in the field of hospital charges. That sort of expert charges for their services and can get very expensive.
Maybe the defendant thinks that your treatment was excessive and unnecessary. If so, then the defendant will have to retain a medical doctor or other health practitioner to prepare the counter affidavit. That sort of expert testimony is even more costly than a billing expert and can cost the defense several thousand dollars for each expert.
So, a defendant must balance the need for obtaining a counter affidavit with the associates costs.
The counter affidavit must be detailed.
Unlike the plaintiff’s affidavit, a counter affidavit must be more detailed. It is not enough that the counter affidavit simple state the the charges are unreasonable or that the treatment is unnecessary. The counter affidavit must state that basis for these conclusions and provide an explanation. Therefore, the counter affidavit tends to be much more lengthy whereas the plaintiff’s affidavit is usually contained in just one page. This is yet another reason why the counter affidavits are more costly than the plaintiff’s affidavit.
Get an Experienced Personal Injury Attorney.

Dallas Personal Injury Attorney
Although you may find this article informative, it is not intended as a substitute for proper legal representation. There are many other “ins and outs” that apply to the use of a billing affidavit. Unless you are a Texas lawyer, you may find yourself unable to address other issues that may come up.
Robert C. Slim has been representing injured clients in the Dallas/ Fort Worth area since 1994 with great success. With dedication to thorough preparation and personal legal representation, Mr. Slim has helped many get the resolution to their injury claims and the compensation they deserve.
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