It will initially be available for residential and buy to let applications with 10-digit mortgage account numbers and is located within the tools section of the Barclays Intermediary Hub.
The lender said it will mean applications can be submitted applications quicker with no documentation or signed declarations required.
It added that rate switches for buy to let mortgages with six-digit account numbers will be coming shortly.
The lender also revealed that 32% of its mortgage switching retention business was originated online as part of its interim results for the first half of 2018.
Mortgage lending up £1.3bn
Barclays also revealed its gross mortgage lending for the six months from January to June rose by £1.3bn to hit £11.3bn, continuing its strong growth from last year.
It saw a notable upturn in higher loan to value (LTV) leading with 8.9% of new deals above 85% LTV, compared to 4.7% last year.
Its mortgage book had grown by around £5.5bn since June 2017 “without impacting the risk profile”, the bank added.
The average loan to value (LTV) on its book is 50% while buy to let made up just 12% of its total loan book.
Barclays UK profit before tax increased to £826m from £634m in the same period last year, however overall Barclays Group profit before tax slumped to £1.66bn from £2.34bn.
This included litigation and conduct charges of £2.0bn principally related to a £1.4bn settlement with the US Department of Justice (DoJ) with regard to Residential Mortgage – Backed Securities and charges of £400m due to Payment Protection Insurance (PPI).
Barclays Group chief executive officer James Staley said the second quarter was the first quarter “for some time with no significant litigation or conduct charges, restructuring costs, or other exceptional expenses which hit our profitability”.
“In effect then, it is the first clear sight of the statutory performance of the business which we have re-engineered over the past two and a half years – Barclays’ transatlantic consumer and wholesale bank – and it is a positive sight.”