Coding guide · 10 min read
ICD-10 Code for Concussion: What S06.0X0A Means
The ICD-10 code for a concussion is S06.0X0A — Concussion without loss of consciousness, initial encounter — and that single code covers the most common situation there is: a first visit for a concussion where nobody was knocked out.
It isn't a one-line answer for everybody, though, because S06.0X0A is one of twelve codes that describe the same injury. The sixth character records whether consciousness was lost and for how long. The seventh records which visit this is. Change either fact and the code changes with it, even though the injury on the table is identical.
This guide lays out the whole S06.0X family with the official titles, what the 7th character does, what the X is doing in the middle of the code, which codes travel alongside it on a claim, and what any of it means if you're holding a bill rather than a chart.
What is the ICD-10 code for a concussion?
The injury itself is coded from subcategory S06.0X in ICD-10-CM, and the code most often used is S06.0X0A, Concussion without loss of consciousness, initial encounter. It is a billable, fully specific code — nothing further needs to be added to make it valid.
S06.0X sits inside category S06, Intracranial injury, which the code set says includes traumatic brain injury. In ICD-10-CM, then, a concussion is filed as a brain injury, not a bump on the head. The entry also carries an "applicable to" note for commotio cerebri, the older Latin name for the same thing.
These codes are also the raw material for national injury surveillance. The CDC counts roughly 214,110 TBI-related hospitalizations in 2020 and 68,663 TBI-related deaths in 2023 from coded records, while noting those figures leave out injuries treated only in an emergency department, urgent care or primary care, or never treated at all — which is most concussions.
What are all the codes in the S06.0X concussion family?
There are twelve billable codes: four sixth-character options, each with three seventh-character options. The sixth answers "was there loss of consciousness, and for how long"; the seventh answers "which encounter is this".
| Code | Official title |
|---|---|
| S06.0X0A | Concussion without loss of consciousness, initial encounter |
| S06.0X0D | Concussion without loss of consciousness, subsequent encounter |
| S06.0X0S | Concussion without loss of consciousness, sequela |
| S06.0X1A | Concussion with loss of consciousness of 30 minutes or less, initial encounter |
| S06.0X1D | Concussion with loss of consciousness of 30 minutes or less, subsequent encounter |
| S06.0X1S | Concussion with loss of consciousness of 30 minutes or less, sequela |
| S06.0X9A | Concussion with loss of consciousness of unspecified duration, initial encounter |
| S06.0X9D | Concussion with loss of consciousness of unspecified duration, subsequent encounter |
| S06.0X9S | Concussion with loss of consciousness of unspecified duration, sequela |
| S06.0XAA | Concussion with loss of consciousness status unknown, initial encounter |
| S06.0XAD | Concussion with loss of consciousness status unknown, subsequent encounter |
| S06.0XAS | Concussion with loss of consciousness status unknown, sequela |
Those titles are the code set's own, from the current S06.0 listing. Two sixth characters look similar and are not: 9 means consciousness was lost but the duration wasn't recorded, while A means it isn't known whether consciousness was lost at all. Code releases change every October, so check the current one before relying on any list, including this.
When is a head injury an emergency rather than a coding question?
Some symptoms after a head injury need emergency care now, not a diagnosis code later. Stop reading and call 911 or get to an emergency department if any of them are present.
The CDC lists among its danger signs in adults a headache that gets worse and does not go away, repeated vomiting, one pupil larger than the other, slurred speech, seizures or convulsions, and losing consciousness, looking very drowsy or being impossible to wake. For a baby or young child the CDC adds signs including crying that will not stop and cannot be soothed, and refusing to nurse or eat.
A quiet first hour proves nothing either: the CDC notes that some concussion symptoms may not appear for hours or days after the injury. Our guide to the symptoms of concussion sets out what is expected and what is not.
What does the 7th character — A, D or S — actually mean?
The 7th character records where the patient is in the episode of care, not how bad the injury was: A while active treatment is happening, D once care has moved into routine follow-up, and S for a later condition the injury caused.
CMS describes the three as: A, initial encounter, used as long as the patient is receiving active treatment for the condition; D, subsequent encounter, used after active treatment, when the patient is receiving routine care during the healing or recovery phase; and S, sequela, for complications or conditions that arise as a direct result of the condition.
"Initial" is the word that trips everybody. It does not mean the first appointment on the calendar — it means active treatment, so a second emergency department visit for the same concussion can still take A while a routine recheck weeks later takes D. The Defense Health Agency's TBI coding guidance handles this by instructing clinicians to use A only for the first visit within the system and D for each subsequent visit while the injury is under 90 days old — one system's operating rule, not a universal one, but a good illustration of how much the choice rides on local policy and documentation rather than on the concussion itself.
Sequela never travels alone. The ICD-10-CM guidelines state that coding a sequela generally requires two codes, with the condition or nature of the sequela sequenced first and the sequela code sequenced second — so S06.0X0S names the concussion that caused the problem and a second code names the problem itself, as in the Defense Health Agency's example pairing it with a code for insomnia. There is no expiry date on it: CMS defines a sequela as the residual effect after the acute phase has ended, with no time limit on when a sequela code can be used.
Why is there an X in the middle of S06.0X0A?
The X is a placeholder, not an abbreviation. It fills an empty character position so the 7th character lands where the system expects to find it.
CMS explains that the placeholder character is used to allow for future expansion and to fill in empty characters when a code shorter than six characters requires a 7th character. The rule the guidelines add is unforgiving: the 7th character must always be the 7th character in the data field, and where a placeholder exists it has to be there for the code to be valid.
So S06.0 is the concussion subcategory, X holds the fifth position open, 0 in the sixth says no loss of consciousness, and A in the seventh says initial encounter. Drop the X and you don't have a shorter code, you have an invalid one.
What does "with loss of consciousness" change, and who decides it?
It changes the sixth character and nothing else. It does not make the concussion a different or more severe diagnosis in the code set — S06.0X0 and S06.0X1 sit side by side in the same subcategory.
A lot of people assume a concussion requires being knocked out. It doesn't. American Family Physician puts it directly: loss of consciousness and amnesia were once considered the hallmarks of concussion, but neither is required for diagnosis. The code set reflects that — "without loss of consciousness" is the first option in the family, not an afterthought — and concussion codes make up the bulk of TBI coding, accounting for roughly 85% of the traumatic brain injuries seen in the Military Health System.
Note where the family stops. The longest span it describes is 30 minutes or less, with a separate code for unspecified duration. Longer periods of unconsciousness get sixth characters that exist elsewhere in category S06 — 31 to 59 minutes, one hour to just under six, six to 24 hours, and beyond — but those intervals belong to the other intracranial injury subcategories, not to S06.0X. And the answer comes from what the clinician documented, which is exactly why sixth characters 9 and A exist.
What other codes get reported alongside a concussion code?
A concussion code often isn't alone on the claim. Category S06 carries instructions pointing to companion codes, and a second code on a bill for one injury is usually one of those doing its job.
The S06 entry says to code also any associated open wound of head (S01.-) or skull fracture (S02.-), and to use an additional code, if applicable, to identify mild neurocognitive disorders due to known physiological condition (F06.7-). Severity gets its own set: the Glasgow Coma Scale codes in the R40.21– to R40.24– range are reported alongside traumatic brain injury codes.
Two exclusions matter. S06 carries an Excludes1 for head injury NOS (S09.90) — the unspecified code and the specific one are alternatives, not partners. S06.0 itself excludes concussion occurring with other intracranial injuries classified in subcategories S06.1- to S06.6- and S06.81- to S06.89-, which are coded to the specified intracranial injury instead. In plain terms: if there is a bleed or swelling too, that gets coded, not the concussion.
External cause codes — how the injury happened — are a separate chapter and a separate question. CMS states there is no national requirement for mandatory external cause code reporting, though it encourages voluntary reporting for injury research. States and payers may take a different line.
What is the difference between S06.0X0A and F07.81?
S06.0X0A codes the injury. F07.81 codes the syndrome that can persist after it. They answer different questions and are not interchangeable.
F07.81 is titled Postconcussional syndrome, and its entry carries an Excludes1 note for current concussion (brain) — the code set does not want a record asserting both at the same encounter, because that would claim the injury is happening now and has already resolved into an aftermath. Our separate guide to what the F07.81 code means and what its Code First instruction requires covers that page's worth of questions in full.
There's no coding rule about when a case crosses from one to the other, and no number of days to look up. The line clinicians think in comes from the literature instead, where persisting symptoms have been defined as those lasting over two weeks in adults and over four weeks in children — a clinical threshold, not a billing one, and never to be quoted as a coding rule. For the arc rather than the codes, our walk-through of the stages of concussion recovery maps the usual sequence.
What does a concussion code mean if you're the patient reading a bill?
It means your clinician recorded a concussion, and which visit this was. That is the entire claim the code makes — it is not a severity score, a prognosis, or a judgment about you.
Three things reliably confuse people. "Initial" on a visit that plainly wasn't your first is the active-treatment definition above, not an error about your history. More than one code for one injury is usually a "code also" instruction being followed, not double-counting. And no scan result behind any of it is normal — imaging isn't what makes the diagnosis, and the AAFP's summary of the CDC guideline is explicit that head CT should not be routinely performed to assess patients with mild TBI.
A diagnosis code also doesn't decide coverage on its own, and nothing here can predict what a given plan will do. What carries weight in paperwork is the documentation behind the code — what was assessed, what was found, and how it changed. Keeping your own dated record of the injury and your symptoms costs nothing and makes that documentation easier to produce accurately. If a claim is denied, the two people who can actually explain it are your clinician's billing office and your plan.
Where can you get assessed for a concussion?
Look for a clinician or program that assesses concussion specifically, not a general appointment that ends in "give it time." Care for concussion that isn't settling is interdisciplinary and individually tailored to the symptom profile — vestibular, vision-oculomotor, behavioral health, cognitive rehabilitation — rather than one protocol for everyone, so who you see changes what you get.
Across the 3,205 verified listings in our directory, 1,117 describe multidisciplinary concussion care, 1,069 offer vestibular and balance assessment, 929 offer neuropsychology or cognitive testing, and 405 offer vision or neuro-optometry. The thin spots are worth knowing before you start calling: only 186 listings offer vision and vestibular work in the same building, and 305 — about one in ten — name headache or migraine as a service. If distance is the obstacle, 521 listings state that they offer telehealth.
If you're not sure which you need, our two-minute specialist quiz narrows it down before you start phoning, and you can search the directory of 3,205 verified concussion providers across 1,010 cities and all 50 states plus DC. Take the code for what it is — a label, correctly applied to something real — then go get the injury behind it looked at properly.
Find a concussion specialist near you
Search 3,205 verified concussion clinics and specialists across all 50 states — filter by services like vestibular therapy, vision therapy, and neuropsychology.
Browse the largest state directories: California (148) · South Carolina (136) · Pennsylvania (125).
Not sure which kind of specialist your symptoms point to? Take the 2-minute specialist quiz →
Frequently asked questions
Is S06.0X0A a billable code on its own?
Yes. S06.0X0A is a billable, fully specific ICD-10-CM code, so nothing further has to be added to make it valid. Other codes may still appear beside it on a claim, because category S06 carries “code also” instructions for things like an associated open wound of the head or skull fracture.
What is the ICD-10 code for a concussion with loss of consciousness?
S06.0X1A is concussion with loss of consciousness of 30 minutes or less, initial encounter. If consciousness was lost but the duration was not documented, the code is S06.0X9-, and if it is not known whether consciousness was lost at all, the code is S06.0XA-. Each of those takes a 7th character of A, D or S.
What is the difference between S06.0X0A and S06.0X0D?
Only the 7th character, which records the episode of care rather than the injury. A is used while the patient is receiving active treatment, and D once treatment has moved into routine care during the healing or recovery phase. The concussion being described is exactly the same.
Is there a separate ICD-10 code for a concussion in a child?
No. The S06.0X family has no pediatric codes and no age split, so a child and an adult with the same documented injury take the same code. What changes the code is whether consciousness was lost, for how long, and which encounter is being recorded.
What is the ICD-10 code for a history of concussion?
There is no code specific to a past concussion, but Z87.820 is “Personal history of traumatic brain injury” and is a billable code. It records that a brain injury happened and has healed, which is a different statement from an active injury code in the S06.0X family or from F07.81 for a syndrome that is still going on.
Do you need an external cause code alongside a concussion code?
CMS states there is no national requirement for mandatory external cause code reporting, though it encourages voluntary reporting because the data is valuable for injury research. Individual states, payers and providers may still require it, so the answer depends on local rules rather than on ICD-10-CM itself.
Educational content only — not a substitute for professional medical advice, diagnosis, or treatment. Reviewed by Jon MacKay, PharmD, BCACP against current clinical guidance; last updated August 2026.