1. Difference of recruitment
Public sector banks recruit mainly through bank exams and public notices. Private banks, on the other hand, prefer campus placements and referrals. For entry level jobs too, private banks usually go through campus placements. You would seldom find a public notice issued by a private bank for recruitments.
2. Difference of vacancies
Public sector banks go by the vacancy rules laid by the government.
There is a certain portion of vacancies reserved for OBCs and SC/STs. There are no reservations in private sector banks.
The reservations make it harder to find a job in a public sector bank.
3. Difference in growth
One of the banes of public sector banks is slow growth. If you get recruited at the entry level in a public sector bank, you would take forever to reach the higher levels. There are certain rules for promotion and salary is fixed according the level you are working at. Promotions in public sector banks are usually not done on merit, but other criteria laid down by the government.
On the other hand, growth can be fast and robust in a private sector bank job. In the private sector, you get promotions on merit, and if you are good, sky is the limit for you.
4. Difference in working environment
Largely, the working environment of private and public sector banks is the same. However, private sector banks are largely more competitive than the public sector banks, although that situation is changing fast. In a private sector bank, you usually have to meet tough targets, and adhere to the deadlines. You could be working longer hours very often in private sector banks in order to meet your targets and deadlines.
The environment is more relaxed in a public sector bank, but that by no means implies you do not have work in the public sector.
5. Difference in pay scale
Largely, the pay scale in private and public sector banks is the same. However, according to recent studies done on the field, it has been seen that public sector banks pay more compared to private sector banks, when the working hours are taken into consideration.
However, since the growth in public sector banks can be slow, the advantage of higher pay scale is usually negated. As for the question, whether to work in a private sector or a public sector bank, the difference between both the sectors is fast diminishing. If you have a choice, go for a bank that offers opportunities for growth, which could be a public sector bank or a private sector bank too.