The comparison of a UX Designer vs. UX Consultant is becoming more relevant, since many professionals are unable to differentiate both terms. The term UX Consultant is gaining popularity and consolidates the adoption of user-centricity in industries outside the typical design-related realm.
First of all, it is important to mention that both professions have similar fields of expertise. Although the lines are blurry, it is still possible to draw a comparison. This following post is based on my personal experience. 

Design Background

The main difference between these two jobs is that a UX Designer is highly specialised on the user-perspective and intends to transform potential pains into pleasing experiences. The user-centricity dictates design-implementations according to UX-principles like understandability, efficiency, intuitive use, and so on. A UX Designer evaluates design decisions, based on empathy for the user and performs expert-level execution of design tasks. He/she operates on a tactical and operational level and needs a design-related education.

Consultancy Background

A UX Consultant on the other hand, deals with both sides of the market and intends to derive long-term strategies that are beneficial for the user and the business. That way a potential blue ocean can be created, making a holistic approach for analysis and evaluation inevitable for this process. A UX Consultant is responsible for the collaboration beyond silos and has to connect various stakeholders. Hereby highlighting the importance of "design as a strategy" on a corporate level, supervising progress and measuring the KPIs. He/She operates on a predominantly strategic level and can have a design-related profession.
However, the skillset has to be interdisciplinary and combine various field of expertise. The qualification is based on the T-shaped persona, which describes the ability to connect an expertise with various other disciplines. This makes the persona particularly suitable for diverse teams, where amplified cooperation and high flexibility is needed.

Check out my C.V. to get to know my professional background. 

The following visualisation is a great summary of the main differences between a UX Designer vs. UX Consultant.

"Comparison UX Designer vs. UX Consultant"
Comparison of a UX Designer and UX Consultant (Micah Bowers et al.)

UX Consultant Skills

If you want to check out what it needs to become a UX Consultant, I invite you to read this blog post.