Is a master's degree needed for a GIS career?
Getting a master degree might be a good thing for several reasons:
You can position yourself as a person with higher qualifications (yet I have seen many organizations asking for diploma papers in Europe and many organizations who did not ask for any papers at all).
You will learn a lot during your studies. Check carefully the curriculum - not all masters are the same. Look for the one that has courses you enjoy most.
Being a European, I can suggest something for Europe if this is applicable in your case. Consider obtaining a MSc on a remote basis, there is a good one in Lund (LUMA GIS), Sweden. It used to be free, but since introduction of tuition fees in Sweden, it costs quite some money to study (even distantly) nowadays. Check the prices at their website here. There should be also some other MSc programs in GIS/geomatics available in Europe. Some of them are not that expensive and I believe there were some that are 1year (most of others will be 2years which will have the impact on the total price for tuition fees and accommodation).
Speaking in terms of competence, you definitely don't need a MSc to get a decent job in GIS or related field. But imho if you will get a chance to spend a year studying, it is worth earning a master degree which will make you more attractive for certain employers. However, from what I've seen there was somewhat a preference for folks with a bachelor degree but at least some work experience comparing to those who have just got masters.
If you won't have a chance to study for a master, consider developing your skills yourself by looking at the Geospatial Management Competency Model which imho gives a good overview of the skills you need to succeed in the GIS/geospatial career. Michalis Avraam has a great blog post for skills you might want to have, too.
The answers that you are going to get for this question are going to be primarily based on personal experience and are also going to vary based on location and as such this question in its current form is not a good format for this site. That being said, in my country (United States) GIS full-time job requirements are normally (I'm generalizing based upon postings I peruse over at the GIS jobs clearinghouse) as follows:
GIS Technician: No degree or associates degree, sometimes bachelor's
GIS Analyst, GIS Developer, GIS Manager, GIS Specialist: Bachelor's degree
GIS Lecturer, GIS Researcher: Master's
So (again this is a sweeping generalization) the only real career that usually asks for a Master's degree is academia in the U.S. If you would like to have the option to serve as an adjunct professor at a University in the U.S. I would pursue a masters, otherwise it is not usually a requirement.
Most employers are looking for experience and not certificates on the wall. But a master's degree gives you experience and confidence to take the job. here is Six Things You Should be Doing to Enhance Your GIS Career. Good Luck !