You were likely performing the new role well before the promotion. I would update your job title to reflect the new position. Also, I would add an accomplishment or two that highlights why your company promoted you to the new role.

You deserve to have the help of a professional resume writer and/or career coach to develop your resume. Without more information from you, there’s a risk of not learning the best approach. Why were you promoted? Why did you leave? Did you leave for another offer? Are you are currently employed? Did you provide appropriate notice prior to leaving your previous company?

You may want to consider consolidating your promotion position and previous position into one listing under your current employer (that shows both titles and combines the dates). This will allow for a full list of accomplishments to be shown and will downplay the promotion time period.

The key will be to highlight the competencies, tasks, and skills you demonstrated that led to your promotion. In 3 to 4 active voice bulleted statements, stack these tasks, skills and competencies under a separate sub-heading simply labeled “Promoted to….” at the very top of that employer’s section in your resume.

Your resume should reflect your position upon departure. Although you do not have any additional accomplishments, any responsibilities that you have taken on can be included with the prefix like “proficient in” or “novice in” . The magic will be in the interview where you must prepare examples of how you have been successful in growth progression and why you were promoted in the first place.