The Hardy-Littlewood inequalities for m-linear forms on p spaces are stated for p > m. In this paper, among other results, we investigate similar results for 1 ≤ p ≤ m. Let K be R or C and m ≥ 2 be a positive integer. Our main results are the following sharp inequalities:T for all m-linear forms T : n p × · · · × n p → K and all positive integers n. (ii) If (r, p) ∈ [2, ∞) × (m, 2m], then n j 1 ,...,jm=1 |T (ej 1 , . . . , ej m )| r 1 r ≤ √ 2 m−1 n max p+mr−rp pr ,0T for all m-linear forms T : n p × · · · × n p → K and all positive integers n. Moreover, the exponents max{(2mr + 2mp − mpr − pr)/2pr, 0} in (i) and max{(p + mr − rp)/pr, 0} in (ii) are optimal. The cases (r, p) = (2m/ (m + 1) , ∞) and (r, p) = (2mp/ (mp + p − 2m) , p) for p ≥ 2m and (r, p) = (p/ (p − m) , p) for m < p < 2m recover the classical BohnenblustHille and Hardy-Littlewood inequalities.Mathematics Subject Classification. 32A22, 47H60.