This study will test the clinical efficacy of an accelerated TMS (accel-TMS) protocol that rapidly addresses PTSD symptoms with 1 week (25 sessions over 5 days) of condensed treatment.

This study will have three phases: an acute phase (1 week of treatments), an extension phase (second week of treatments), and a long-term observational follow-up phase of 6 months.

The acute phase will be a three-arm randomized sham-controlled trial with: Arm 1 = active left dl-PFC accel-TMS; Arm 2 = active dm-PFC accel-TMS; and Arm 3 = sham accel-TMS (half with sham dl-PFC and half with sham dm-PFC coil positioning).

In the subsequent extension phase, all participants will receive active left dl-PFC accel-TMS. For the follow-up phase, clinical outcomes will be assessed at 1-month, 3-months, and 6-months. The primary outcome measure will be the CAPS-5.

A range of other secondary outcome measures will also be included.

Inclusion:

1. Adults age 18 years to 65 years old.
2. Meets DSM-5 criteria for PTSD with a PCL-5 score > 33
3. No changes in psychotropic medication (if taking psychotropic medication) and/or changes in supportive psychotherapy for 1 month prior to initial visit; and clinically appropriate to maintain stable treatment regimen for duration of trial.
4. Clinically competent to give informed written consent and ability to understand study procedures and to comply with them for the entire length of the study

Exclusion:

1. Medical contraindication for neuromodulation (e.g., ferrous metal in head, seizure disorder, brain tumor, stroke, aneurysm, multiple sclerosis, etc.).
2. Active substance use disorder in last 3 months or any current substance use that puts the participant at increased risk or significant impairment.
3. Dementia or other cognitive disorder making unable to engage in treatment.
4. Any history or diagnosis of Schizophrenia, Schizoaffective Disorder, Delusional Disorder or other psychotic illness that precludes safe participation in trial.
5. Suicidal risk that precludes safe participation defined as clinical impression that the participant is at significant risk for suicide.
6. OCD cannot be the primary disorder but can have OCD symptoms.
7. Inability to stop taking any medication that significantly lowers the seizure threshold (e.g., tricyclic antidepressants, clozapine, etc.)
8. Current, planned, or suspected pregnancy
9. Unstable medical conditions or any current medical condition that could preclude being able to safely participate in TMS treatment (e.g., unstable metabolic abnormality, unstable angina, etc.)
10. Severe Traumatic Brain Injury
11. We will exclude non-English speakers because of the need for rapid communication during the delivery of treatments.
12. Significant ongoing litigation or claims that impact research activities, as determined by the research study team. (Research may especially be impacted when mental health or pain is being evaluated for litigation or claims, such as civil and criminal cases, disability claims and worker's compensation).
13. Prior known active TMS of dorsolateral prefrontal cortex or dorsomedial prefrontal cortex or electroconvulsive therapy (ECT) -

Blinding Procedures The participants, PI, Research Staff involved in TMS treatment, and staff performing the study procedures will be blinded to the participant's dl-PFC protocol assignment throughout the study.