The integrable function universal for classes $$L^{p}[0,1]$$ , $$p\in\left(0,1\right)$$ with respect to the Walsh system is constructed in terms of signs. The Fourier–Walsh series of this function converges everywhere in $$(0,1)$$ and in the metrics $$L^{p}[0,1]$$ , $$p\in(0,1)$$ , and its Fourier coefficients by the Walsh system are in decreasing order. After selecting the appropriate signs for its Fourier coefficients, the newly obtained series will be universal with respect to permutations in $$L^{p}[0,1]$$ , $$p\in\left(0,1\right)$$ .