The change of cooperativity of FH···Cl⁻ hydrogen bonds upon sequential addition of up to six FH molecules to the Cl⁻ first coordination sphere is investigated. The geometry of clusters [(FH)_nCl]⁻ (n = 1…6) was calculated (CCSD/aug-cc-pVDZ) and compared with [(FH)_nF]⁻ clusters. The geometry is determined by the symmetry-driven electrostatic requirements and also by the fact that formation of each new FH···Cl⁻ bond creates a depression in the chlorine's electron cloud on the opposite side of Cl⁻ (σ-hole), which limits the range of directions available for subsequent H-bond formation. The mutual influence of FH···Cl⁻ hydrogen bonds is anticooperative—the addition of each FH molecule weakens H-bonds by 23–16% and decreases their covalent character (as seen by LMO-EDA decomposition and QTAIM analysis). Anticooperativity effects could be tracked by spectroscopic parameters (frequency of local HF mode ν_FH, chemical shift δ_H, spin–spin coupling constants ¹J_FH, ^1hJ_HCl, ^2hJ_FCl and nuclear quadrupolar constants χ_18F, χ_D, and χ_35Cl.