  In this paper, we investigate the cosmological implications and constraints
of Weyl-type $f(Q, T)$ gravity. This theory introduces a coupling between the
non-metricity $Q$ and the trace $T$ of the energy-momentum tensor, using the
principles of proper Weyl geometry. In this geometry, the scalar non-metricity
$Q$, which characterizes the deviations from Riemannian geometry, is expressed
in its standard Weyl form $\nabla _{\mu }g_{\alpha \beta }=-w_{\mu }g_{\alpha
\beta }$ and is determined by a vector field $w_{\mu }$. To study the
implications of this theory, we propose a deceleration parameter with a single
unknown parameter $\chi$, which we constrain by using the latest cosmological
data. By solving the field equations derived from Weyl-type $f(Q, T)$ gravity,
we aim to understand the behavior of the energy conditions within this
framework. In the present work, we consider two well-motivated forms of the
function $f(Q, T)$: (i) the linear model represented by $f(Q, T) = \alpha Q +
\frac{\beta}{6\kappa^2} T$, and (ii) the coupling model represented by $f(Q, T)
= \frac{\gamma}{6H_0^2 \kappa^2} QT$, where $\alpha$, $\beta$, and $\gamma$ are
free parameters. Here, $\kappa^2 = \frac{1}{16\pi G}$ represents the
gravitational coupling constant. In both of the models considered, the strong
energy condition is violated, indicating consistency with the present
accelerated expansion. However, the null, weak, and dominant energy conditions
are satisfied in these models.
