Probate is frequently required for the administration of a person’s estate, and some institutions require a Grant of Representation no matter the size of the estate.  You may find, however, that you do can manage the estate without probate if the following situations apply:
The person owned the assets in their estate jointly with another person and so they will automatically pass to the surviving spouse or civil partner. Unless jointly owned, a Grant will always be required when property is involved.
The person has a "small estate"- while there is no specific amount that constitutes a small estate and this will vary from institution to institution, this can range from between £10,000 to £50,000. We would always recommend you discuss this with the institution in question as they may have their own limits and could be flexible depending on the situation.
The person was insolvent.