Hampshire was sentenced on Monday.
David Hampshire, of Osborne Square, stole the items from customers while in their homes to use the toilet.
The 28-year-old first targeted a number of customers in the Becontree area in September, October, and November last year.
On each occasion, he would clean the windows, then come back the following day to collect payment.
But after being paid, he would ask to use the toilet and would steal jewellery while left unsupervised.
The first victim contacted the window cleaning company’s owner who vowed to terminate Hampshire’s contract.
But he went on to steal from three other customers and was arrested by police in November.
Hampshire was charged with four counts of burglary but initially denied being responsible.
But, on the first day of his trial at Snaresbrook Crown Court last month, he changed his plea to guilty.
On Monday, he was jailed for five years and four months.
PC Raheel Sarwar, who led the investigation, said: “Hampshire deliberately targeted elderly individuals who trusted him and they have been left shaken by his deceitful actions.
“We hope this sentence provides them with some level of closure and shows we are committed to getting individuals like Hampshire off our streets.”
Tags: Dagenham, Becontree