If the academic requirements are not met, are there any alternative criteria like letters of recommendation or work experience that can help in admission to these universities in UK for a Master's/Postgraduate?

If your grades fall short of a UK master's requirement, you are not automatically out of the running. Admissions tutors at many universities, especially for business, vocational, and creative courses, will weigh strong work experience and references alongside your transcript. Your job is to build a case that shows the shortfall does not reflect your real ability.

What Each Alternative Criterion Actually Does

Where Universities Draw The Line

• Highly selective institutions such as Oxford, Cambridge, Imperial, and UCL rarely compromise on hard grade cutoffs given the volume of fully qualified applicants.
• Less competitive, newer universities are far more accommodating of professional backgrounds and case by case reviews.
• If you miss the requirement by a narrow margin, for example 73 percent against a 75 percent cutoff, strong experience and references can genuinely tip the decision your way.

My Advice

Email the admissions office directly, state your exact grade and how far it falls short, and ask in writing whether they operate a discretionary or holistic review, since that single answer tells you whether it is worth building a full case with experience and references.