The charity, whose annual fundraising day takes place on 16 November, has been criticised in the past by the Institute of Fundraising and donor information website Intelligent Giving for its promise because it does not take administration costs into account.
Last month, the charity adopted a revised slogan that says: "For every penny you donate, a penny will go towards projects helping disadvantaged children and young people in the UK. We are able to make this promise because the charity uses its investment income to cover all operational costs."
The new slogan was widely welcomed (Third Sector, 12 September), but the BBC has since broadcast a two-minute promotional film that included a voiceover from Terry Wogan saying that every penny donated would be used to help disadvantaged children in the UK.
A spokeswoman for Children in Need said the charity was committed to being transparent and using the full explanation when "editorially appropriate". But she added: "The time constraints of a short promo meant that the longer explanation of our fundraising promise was not used."
She said the charity had explained on all fundraising material and its website how it uses investment income to cover operational costs.
Megan Pacey, director of policy and campaigns at the Institute of Fundraising, said critics of the charity should "cut them some slack".
She added: "The practicality of live TV means that you can't go into a 15-line explanation of how the money will be spent."