Guy's and St Thomas' NHS Foundation Trust has achieved the highest ratings possible in the Care Quality Commission's annual health check.
The trust was rated as 'excellent' for quality of services, and 'excellent' for the quality of financial management. Hospitals can be deemed to be excellent, good, fair or weak.
Last year the trust blamed glitches with a new NHS computer system for a dip in performance which led to a 'good' rating for services.
The trust says that it performed outstandingly in nearly all of the clinical targets being assessed. These included top scores for safety and cleanliness, standards of care, dignity and respect, keeping the public healthy and providing good management.
The trust also met all its infection control targets, with fewer cases of MRSA and C. difficile than anticipated by the commission.
SE1's two hospitals also achieved the maximum possible score against the NHS's 13 national priorities which include cancer waiting times, stroke care, patient experience and staff satisfaction.
However, the hospitals were deemed to have "under-achieved" on measures to tackle cancelled operations and inpatient waiting times.
Hospital bosses boast that they achieved a £25.5 million surplus that will be reinvested in plans to improve services and the hospital environment for patients.
"Our performance in this year's annual health check has been very encouraging with impressive results in a number of key areas affecting our patients," says chief executive Ron Kerr.
"I am particularly pleased to have once again achieved a double excellent rating as I feel this accurately reflects how well we are performing as a trust.
"Throughout the year there are many different national surveys and ratings, but the Care Quality Commission health check is the most comprehensive and important performance indicator, and so to attain the best score possible is hugely satisfying.
"I'd like to take this opportunity to pay credit to all our staff because they are the ones giving patients such high levels of care, and helping us achieve these results."
Chief nurse Eileen Sills added: "We have already made significant progress this year to improve our performance on reducing cancelled operations and the number of people who wait longer than necessary for treatment, as this is important to our patients."